processing: inspectable per-run stop seam for lifecycle fire

Unify halt and fire cancellation by verified run identity with durable first-owner receipts and shared deadlines. Integrate the instance control with the current host, library and tester-socket paths. Focused nine-file evidence is 62 passing tests; broad suites, mutants and review remain pending.

Containerfile

@@ -22,6 +22,7 @@ RUN npm ci --ignore-scripts
 # runtime adapters.
 COPY contracts /opt/mosaic/contracts
 COPY src /opt/mosaic/src
+COPY packages/processing-control/src/state.mjs packages/processing-control/src/entrypoint.mjs /opt/mosaic/processing-control/
 COPY adapters /opt/mosaic/adapters
 RUN chmod 0555 /opt/mosaic/contracts /opt/mosaic/contracts/* \
     && chmod 0555 /opt/mosaic/src /opt/mosaic/src/*.sh \

compose.yaml

@@ -38,6 +38,8 @@ services:
     volumes:
       # Configured runtime state root (from config.json dataRoot).
       - ${MOSAIC_DATA_ROOT:?MOSAIC_DATA_ROOT must be set by scripts/load_config (run via scripts/*.sh)}:/var/lib/mosaic
+      # The whole control directory is protected against unlink and rename-over replacement.
+      - ${MOSAIC_DATA_ROOT:?MOSAIC_DATA_ROOT must be set by scripts/load_config (run via scripts/*.sh)}/control:/var/lib/mosaic/control:ro
       # Runtime credential only: pi auth file mounted READ-ONLY.
       # Never copied into the image.
       - ${PI_AUTH_FILE:-/home/jwoltje/.pi/agent/auth.json}:/home/node/.pi/agent/auth.json:ro

docs/TOOLS.md

@@ -276,11 +276,25 @@ scripts/mosaic follow --thread <thread> [--tester]
 scripts/mosaic stop <run>
 scripts/mosaic launches off | on [--business <id>]
 scripts/mosaic launches list [--json]
+scripts/mosaic halt | resume [--business <id>]
+scripts/mosaic processing status [--business <id>] [--json]
 scripts/bus-service.sh [--instance NAME] render [--copy ID [--copies DIR]] [--pm] [--claude PATH]
 scripts/bus-service.sh [--instance NAME] install [--copy ID [--copies DIR]] [--pm] [--dir DIR] [--no-reload] [--claude PATH]
 scripts/bus-service.sh [--instance NAME] uninstall | status <business>
 ```
 
+The instance processing switch is separate from per-business launches off/on.
+`mosaic halt` durably stops managed processing across every business in the
+selected configuration's data root. The bus stays up for reads and human
+recovery. `mosaic processing status --json` reports settled, pending or unknown
+stops; `mosaic resume` checks the current generation and refuses pending stops.
+Only the existing human proof can write it, independently of channel settings.
+A missing/invalid state is never off: use halt, then resume; an unsafe control
+parent needs operator repair. Unknown task/remote outcomes are not retried.
+Native diagnostic seats remain available. First activation must stop old
+processing before trusted initialization and align the image/read-only control
+mount. This is a separate approved window, never a build step.
+
 The human commands read and resolve through the broker's human transport
 (`packages/bus/src/human-cli.mjs`), never the SQLite file. They refuse inside
 an agent run, except the forms that take `--tester` (rows 110, 175 and 184), which

packages/bus/README.md

@@ -935,3 +935,25 @@ narrow cross-instance reach, not reach within one instance.
 
 The Console provenance option trusts verified code and process metadata, not an independent
 bus-side OIDC exchange. That trade must be approved, not hidden behind the phrase zero trust.
+
+## Durable instance processing control
+
+`processing.status` is an authorized read. `processing.halt` ({}) and
+`processing.resume` ({generation}) require the existing human proof before
+validation or effects. They are management verbs independent of channels and
+never tester or role grants. The strict state under the resolved dataRoot's
+control/ directory is authoritative; reserved processing.halt/resume/stop
+actions mirror its durable transitions and write-once stop receipts with
+verified human and generation. Generic event writers cannot forge them. No
+schema change is needed. Invalid state refuses work and leaves control reads
+and human recovery reachable. Halt then resume repairs an invalid leaf; an
+unsafe parent is not automatically repaired.
+
+The bus remains a read/control service while new agent work, tracker polling,
+notifications and launches pause. Narrow exit cleanup remains possible. Every
+managed starter carries a generation and publishes identity before releasing
+work. Stops inspect root/boot/start identity or generated container id/labels,
+TERM concurrently, then KILL after five seconds and observe for two more.
+Unknown targets remain visible and prevent resume. Existing run evidence is
+not synthesized or rewritten. First activation stops old processing before
+trusted initialization and aligns the copy and image in the human's window.

packages/bus/src/broker.mjs

@@ -1,5 +1,6 @@
 import { randomUUID, randomBytes, createHash } from 'node:crypto';
-import { isAbsolute } from 'node:path';
+import { isAbsolute, dirname } from 'node:path';
+import { initializeControl, processingStatus } from '../../processing-control/src/state.mjs';
 import { NAME as HARNESS_NAME } from '../../plugins/src/kinds.mjs';
 import { loadRequirements } from '../../tasks/src/requirements.mjs';
 import { MERGE, LandingRefusal, readLanding } from './landing.mjs';
@@ -296,11 +297,19 @@ export class Broker {
   // Row 125 (#1619, REQ-LIMIT-4): a run a limit stops, by business:run, until its next receive or state.
   #stops = new Map();
   #clock = 0;
+  #processing;
   // credentialStatus is the runtime's metadata-only Credentials.status(); the broker never gets use().
-  constructor({ store, businesses, secretCheck = () => {}, credentialStatus = () => [], organization = null, project = null, library = null, usage = null, limits = null, harnessOn = null, credentialVerbs = null, hostGrant = null, hostKeys = null }) {
+  constructor({ store, businesses, secretCheck = () => {}, credentialStatus = () => [], organization = null, project = null, library = null, usage = null, limits = null, harnessOn = null, credentialVerbs = null, hostGrant = null, hostKeys = null, processing = null }) {
     if (!object(businesses) || !Object.keys(businesses).length) fail('invalid-business');
     this.#businesses = structuredClone(businesses);
     this.#store = store;
+    // A Broker is a trusted host startup, including in-process hosts. Never repair an existing state as off.
+    const dataRoot = dirname(store.directory);
+    try { initializeControl(dataRoot); } catch (e) {
+      if (!e.code?.startsWith('processing-')) throw e;
+      // Keep the control socket and the human's conservative halt repair available.
+    }
+    this.#processing = processing ?? { read: () => processingStatus(dataRoot) };
     this.#secretCheck = secretCheck;
     this.#credentialStatus = credentialStatus;
     this.#organization = organization;
@@ -368,6 +377,83 @@ export class Broker {
       }
     }
   }
+  #processingState() {
+    try {
+      const state = this.#processing.read();
+      if (!object(state) || (state.invalid === true
+        ? ![true, null].includes(state.halted) || typeof state.code !== 'string' || !state.code.startsWith('processing-')
+        : typeof state.halted !== 'boolean' || state.version !== 1 || typeof state.generation !== 'string' ||
+          !/^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/.test(state.generation)))
+        fail('processing-state-invalid');
+      return state;
+    }
+    catch (e) {
+      if (e.code?.startsWith('processing-')) return { halted: true, invalid: true, code: e.code };
+      fail('processing-state-invalid');
+    }
+  }
+  #processingWork() {
+    const state = this.#processingState();
+    if (state.invalid) fail(state.code);
+    if (state.halted) fail('processing-halted');
+    return state;
+  }
+  #processingGate(s, verb) {
+    if (s.human || s.reader || s.tester) return;
+    if (!['inbox', 'agents', 'tasks', 'trail', 'decisions', 'replies', 'messages', 'state', 'usage',
+      'requirements', 'spec.read', 'project.list', 'project.files', 'project.file', 'library.file', 'library.status',
+      'thread.list', 'thread.messages', 'names', 'instances', 'routes', 'hosts.status',
+      'processing.status', 'role.release', 'usage.end'].includes(verb)) this.#processingWork();
+  }
+  reconcileProcessing() { this.#processingMirror(this.#processingState()); }
+  recordProcessingStop(stop) {
+    if (typeof this.#processing.stopReceipts !== 'function') fail('not-configured');
+    const state = this.#processingState();
+    if (!state.halted || state.invalid || stop?.generation !== state.generation) fail('reserved-event');
+    const stored = this.#processing.stopReceipts(state.generation).find(r => r.id === stop.id);
+    if (!stored || JSON.stringify(stored) !== JSON.stringify(stop)) fail('reserved-event');
+    this.#store.transaction(() => {
+      const body = { action: 'processing.stop', human: state.human, scope: 'instance', ...stored };
+      const old = this.#store.get('SELECT body FROM events WHERE id=?', stored.id);
+      if (old) {
+        if (old.body !== JSON.stringify(body)) fail('processing-audit-conflict');
+        return;
+      }
+      this.#event({ business: state.business, role: null, run: null }, 'action.allowed', body, stored.runtime, stored.id);
+    });
+  }
+  #processingMirror(state) {
+    if (!state?.operation || state.invalid) return;
+    const action = state.halted ? 'processing.halt' : 'processing.resume';
+    this.#store.transaction(() => {
+      const old = this.#store.get('SELECT business,kind,body FROM events WHERE id=?', state.operation);
+      if (old) {
+        const body = JSON.parse(old.body);
+        if (old.business !== state.business || old.kind !== 'action.allowed' || body.action !== action ||
+            body.operation !== state.operation || body.human !== state.human) fail('processing-audit-conflict');
+        return;
+      }
+      this.#event({ business: state.business, role: null, run: null }, 'action.allowed', {
+        action, operation: state.operation, generation: state.generation, human: state.human,
+        at: state.at, recovered: state.recovered, scope: 'instance',
+      }, state.generation, state.operation);
+    });
+  }
+  async #requestProcessing(s, verb, args) {
+    try {
+      this.#human(s);
+      keys(args, verb === 'processing.halt' ? [] : ['generation'], verb === 'processing.halt' ? [] : ['generation']);
+      const method = verb === 'processing.halt' ? 'halt' : 'resume';
+      if (typeof this.#processing[method] !== 'function') fail('not-configured');
+      this.#processingMirror(this.#processingState());
+      const result = await this.#processing[method]({ ...args, business: s.business, human: s.human });
+      this.#processingMirror(result);
+      this.#secretCheck(result);
+      return result;
+    } catch (e) {
+      throw this.#refused(s, e.code?.startsWith('processing-') ? new BusError(e.code) : e, { verb, args }, 'outcome-unknown');
+    }
+  }
   #now() {
     this.#clock = Math.max(Date.now(), this.#clock + 1);
     return new Date(this.#clock).toISOString();
@@ -581,6 +667,7 @@ export class Broker {
     };
     // A run an earlier broker bound is bound again unchanged (the host's recover()), even after its
     // harness was switched off, so it can be ended.
+    if (!old) this.#processingWork();
     if (!old && !this.#harnessOn(record.business, record.harness)) fail('invalid-harness');
     if (old) {
       if (old.actor_role !== record.role || old.body !== JSON.stringify(body)) fail('launch-record-mismatch');
@@ -654,7 +741,7 @@ export class Broker {
     const s = this.#session(cap);
     return { business: s.business, role: s.role, run: s.run, human: s.human || null };
   }
-  #event(s, kind, body, subject = null) {
+  #event(s, kind, body, subject = null, eid = randomUUID()) {
     this.#secretCheck({ kind, body, subject });
     if (
       (kind.startsWith('action.') || kind.startsWith('review.')) &&
@@ -662,7 +749,6 @@ export class Broker {
       subject !== (body.task_ref ?? body.target)
     )
       fail('task-subject-required');
-    const eid = randomUUID();
     this.#store.run(
       'INSERT INTO events(id,at,business,kind,actor_role,actor_run,subject,body) VALUES(?,?,?,?,?,?,?,?)',
       eid,
@@ -1599,6 +1685,7 @@ export class Broker {
     return { tasks, total: matched.length, next: rest.length > limit ? tasks.at(-1).task_ref : null };
   }
   #checkAuthority(s, action, context = {}) {
+    this.#processingWork();
     this.#agent(s);
     return this.#authorityFor(s, action, context);
   }
@@ -1716,6 +1803,7 @@ export class Broker {
   // Row 93: the bus host's git socket asks before it takes a push's bytes. Nothing is recorded
   // unless it refuses: the push is recorded, and its authority consumed, once the ref moved.
   checkPush(cap, task_ref) {
+    this.#processingWork();
     const s = this.#session(cap);
     return this.#store.transaction(() => {
       this.#agent(s);
@@ -1752,6 +1840,7 @@ export class Broker {
   // project the landing uses. A refusal is a code; nothing is recorded unless it refuses.
   // The ticket names the landing to recordLand and landRefused, which may run after the run ended.
   checkLand(cap, args) {
+    this.#processingWork();
     const s = this.#session(cap);
     return this.#store.transaction(() => {
       keys(args, ['task_ref', 'decision'], ['task_ref', 'decision']);
@@ -2029,6 +2118,7 @@ export class Broker {
   // Row 93: what the git socket's fetch for a reviewer may send, from the review.requested event the
   // reviewer cites. The caller must hold review.verdict and be the request's reviewer. Trusted host only.
   reviewFetch(cap, { task_ref, request } = {}) {
+    this.#processingWork();
     const s = this.#session(cap);
     return this.#store.transaction(() => {
       this.#agent(s);
@@ -2056,7 +2146,7 @@ export class Broker {
     return this.#store.transaction(() => {
       this.#agent(s);
       if (['human.input', 'launch.revoked', 'launch.restored', ...REVIEW_KINDS].includes(kind)) fail('reserved-event');
-      if (kind === 'action.allowed' && ['git.push.working', MERGE].includes(body?.action)) fail('reserved-event');
+      if (kind === 'action.allowed' && ['git.push.working', MERGE, 'processing.halt', 'processing.resume', 'processing.stop'].includes(body?.action)) fail('reserved-event');
       if (kind === 'action.allowed' && grantName(body)) fail('reserved-event');
       return this.#event(s, kind, body, subject);
     });
@@ -2179,6 +2269,13 @@ export class Broker {
       const args = request.args ?? {};
       if (!object(args)) fail('invalid-request');
       this.#secretCheck(args);
+      if (request.verb === 'processing.halt' || request.verb === 'processing.resume')
+        return this.#requestProcessing(s, request.verb, structuredClone(args));
+      if (request.verb === 'processing.status') {
+        keys(args, []);
+        return this.#processingState();
+      }
+      this.#processingGate(s, request.verb);
       // Row 213 (C2-08, Case 2 design 5.1 M6): a creative role has no free-text decision channel. It
       // runs before the spec-cited branch below, so a cited raise refuses too.
       if (request.verb === 'decision.raise' && !s.human && !s.tester &&
@@ -2479,6 +2576,7 @@ export class Broker {
   async requestTask(cap, request, handler) {
     const s = this.#session(cap);
     try {
+      this.#processingWork();
       keys(request, ['verb', 'args'], ['verb']);
       if (!TASK_VERBS.includes(request.verb)) fail('unknown-verb');
       const args = request.args ?? {};
@@ -2516,6 +2614,7 @@ export class Broker {
     let args;
     try {
       keys(request, ['verb', 'args'], ['verb']);
+      this.#processingWork();
       if (!verb) fail('unknown-verb');
       args = request.args ?? {};
       const field = verb === 'web.search' ? 'query' : 'url';
@@ -2544,7 +2643,8 @@ export class Broker {
     let out;
     try {
       onAdmit();
-      out = await service.handle(verb, args);
+      out = await (typeof this.#processing.work === 'function'
+        ? this.#processing.work(() => service.handle(verb, args)) : service.handle(verb, args));
     } catch {
       complete({ outcome: 'failed' });
       throw refuse(new BusError('web-failed'));
@@ -2571,6 +2671,7 @@ export class Broker {
     };
     let a, entry, timeout, bound;
     try {
+      this.#processingWork();
       keys(request, ['verb', 'args'], ['verb']);
       if (!HOST_VERBS.includes(request.verb)) fail('unknown-verb');
       a = request.args ?? {};

packages/bus/src/client.mjs

@@ -27,7 +27,7 @@ export class Client {
         socket.destroy();
         error ? reject(error) : resolve(value);
       };
-      socket.setTimeout(this.timeout, () => end(new BusError('outcome-unknown')));
+      socket.setTimeout(['processing.halt', 'processing.resume'].includes(verb) ? Math.max(this.timeout, 20000) : this.timeout, () => end(new BusError('outcome-unknown')));
       socket.on('connect', () => socket.write(request));
       socket.on('error', () => end(new BusError('outcome-unknown')));
       socket.on('end', () => end(new BusError('outcome-unknown')));

packages/bus/src/runtime.mjs

@@ -23,6 +23,9 @@ import { inspectInterpreter, recordInterpreterStart } from './interpreter.mjs';
 import { createPeerReader } from './peercred.mjs';
 import { createUsage } from './usage.mjs';
 import { createLimits } from './limits.mjs';
+import { createProcessing } from '../../processing-control/src/coordinator.mjs';
+import { discordProcessingHooks } from '../../discord/src/processing.mjs';
+import { createContainerStopper } from '../../processing-control/src/containers.mjs';
 // Trusted host API. S1 supplies resolved definitions, S6 supplies launch records and ends them.
 // Human limits writes use the shared organization writer behind the verified transport.
 // `tasks` is S3's adapter factory: ({broker, credentials, businesses}) => {handle, timeout, close}.
@@ -91,7 +94,7 @@ export async function startBroker({
       || (Object.hasOwn(librarySync, 'intervalMs') && !(Number.isSafeInteger(librarySync.intervalMs) && librarySync.intervalMs > 0))
       || (Object.hasOwn(librarySync, 'configDir') && typeof librarySync.configDir !== 'string')))
     throw new BusError('invalid-host-request');
-  let store, credentials, server, adapter, syncTimer = null, syncPass = null;
+  let store, credentials, server, adapter, processing, syncTimer = null, syncPass = null;
   try {
     const references = {};
     for (const [business, b] of Object.entries(businesses)) {
@@ -138,11 +141,20 @@ export async function startBroker({
     const withTokens = (id, result) => ({ ...result, tokens: limits.report(id) });
     // Row 210 (#1707, design D7 step 6) and row 234 (#1740, r6 E2): the run dir and the host enrollment half.
     const runRoot = organization ? join(organization.dir, 'secrets', 'run') : null;
+    let broker;
+    processing = createProcessing({ dataRoot, ...discordProcessingHooks(dataRoot), containerStop: createContainerStopper({ dataRoot }),
+      onTransition: () => broker.reconcileProcessing(),
+      onStop: stop => broker.recordProcessingStop(stop),
+      log: line => process.stderr.write(`${line}\n`),
+    });
     // C2-04: mirrors are host state, never session checkouts. An unsafe
     // existing mirror refuses startup before a socket can become ready.
     for (const business of Object.values(businesses))
       for (const [project, entry] of Object.entries(business.projects ?? {}))
-        if (entry.kind === 'library') await libraryModule.ensureMirror({ business, project, dataRoot });
+        if (entry.kind === 'library') {
+          try { await processing.work(() => libraryModule.ensureMirror({ business, project, dataRoot })); }
+          catch (e) { if (!e.code?.startsWith('processing-')) throw e; }
+        }
     // C2-03a: the slot is <configDir>/secrets/<business>/library-gitea (design 10 step 4). Sync only
     // checks that it is there; the askpass helper reads it.
     const slotDir = librarySync?.configDir ?? organization?.dir ?? null;
@@ -150,10 +162,11 @@ export async function startBroker({
       slot: slotDir ? join(slotDir, 'secrets', business.id, libraryModule.SLOT) : null,
       ...(librarySync ? { command: librarySync.command } : {}),
     });
-    const broker = new Broker({
+    broker = new Broker({
       hostGrant: runRoot ? hostGrant({ configDir: organization.dir, runRoot }) : null,
       // Row 235 (#1741, r6 X4, X5): the grant executor's claim, register and issue, never use().
       hostKeys: storeRoot ? grantKeys({ credentials, storeRoot }) : null,
+      processing,
       usage,
       limits,
       store,
@@ -161,12 +174,12 @@ export async function startBroker({
       library: {
         readFile: context => libraryModule.readLibraryFile({ ...context, dataRoot }),
         status: context => libraryModule.libraryStatus({ ...context, dataRoot }),
-        sync: (context, { accept }) => libraryModule.sync({ ...context, dataRoot }, { ...syncOptions(context.business), accept }),
+        sync: (context, { accept }) => processing.work(() => libraryModule.sync({ ...context, dataRoot }, { ...syncOptions(context.business), accept })),
         LibraryError: libraryModule.LibraryError,
       },
       project: {
         readSpec: context => projectModule.readSpec({ ...context, dataRoot }),
-        writeRecord: context => projectModule.writeRecord({ ...context, dataRoot }),
+        writeRecord: context => processing.work(() => projectModule.writeRecord({ ...context, dataRoot })),
         listFiles: context => projectModule.listProjectFiles({ ...context, dataRoot }),
         readFile: context => projectModule.readProjectFile({ ...context, dataRoot }),
         writeFile: context => projectModule.writeHumanFile({ ...context, dataRoot }),
@@ -205,6 +218,13 @@ export async function startBroker({
         }
       },
     });
+    broker.reconcileProcessing();
+    processing.start();
+    const processingWork = () => {
+      const state = processing.read();
+      if (state.invalid) throw new BusError(state.code);
+      if (state.halted) throw new BusError('processing-halted');
+    };
     // Process identities must be supplied for every managed run when using the human transport.
     const launchRecords = [];
     function bindLaunch(r) {
@@ -222,7 +242,7 @@ export async function startBroker({
     const bound = launches.map(bindLaunch);
     const readCaps = readers.map((business) => ({ business, cap: broker.bindReader({ business }) }));
     if (tasks) {
-      adapter = await tasks({ broker, credentials, businesses });
+      adapter = await tasks({ broker, credentials, businesses, processing });
       if (typeof adapter?.handle !== 'function' || !Number.isSafeInteger(adapter.timeout) || adapter.timeout < 1)
         throw new BusError('invalid-adapter');
     }
@@ -241,9 +261,18 @@ export async function startBroker({
       console: fileURLToPath(new URL('../../webui/src/cli.mjs', import.meta.url)),
     };
     const path = join(store.directory, 'broker.sock');
+    // The existing host executor owns SSH and its key lifecycle. Combine its revocation
+    // signal with processing cancellation without changing its proof or credential entry points.
+    const host = runRoot ? hostExecutor({ root: runRoot, credentials: {
+      busy: (...args) => credentials.busy(...args),
+      useFor: (session, name, fn, options) => credentials.useFor(session, name, (token, meta) =>
+        fn(token, { ...meta, signal: meta.signal
+          ? AbortSignal.any([meta.signal, processing.signal()]) : processing.signal() }), options),
+    } }) : null;
     server = await serve({
       web: (business) => web.get(business) ?? null,
-      host: runRoot ? hostExecutor({ credentials, root: runRoot }) : null,
+      host: host ? { busy: (...args) => host.busy(...args),
+        run: (...args) => processing.work(() => host.run(...args)) } : null,
       tasks: adapter ? { handle: adapter.handle, timeout: adapter.timeout } : null,
       broker,
       path,
@@ -297,11 +326,11 @@ export async function startBroker({
       const { business, project, fork, user, source, dst } = broker.publishTarget(ticket);
       const entry = { state: 'running' };
       remotes.set(ticket, entry);
-      withGitea(ticket, (token) =>
+      processing.work(() => withGitea(ticket, (token) =>
         publishRemote({ repo: workingRepo(dataRoot, business, project), fork, user, source, dst, token, tls: publishTls }).catch((e) => {
           throw e instanceof WorkingError ? new BusError(e.code) : e;
         }),
-      ).then(
+      )).then(
         (r) => Object.assign(entry, { state: 'pushed', ...r }),
         (e) => {
           // Not a refusal: the error's name and code only, never a message that could carry git's output.
@@ -374,7 +403,13 @@ export async function startBroker({
         }
       }
     };
-    const tick = () => { if (!syncPass) syncPass = syncAll().finally(() => { syncPass = null; }); };
+    const tick = () => {
+      const state = processing.read();
+      if (!syncPass && !state.halted && !state.invalid)
+        syncPass = processing.work(syncAll).catch(e => {
+          if (!e.code?.startsWith('processing-')) syncLog({ event: 'library-sync-refused', code: 'library-sync-failed' });
+        }).finally(() => { syncPass = null; });
+    };
     if (timed.length) {
       tick();
       syncTimer = setInterval(tick, librarySync?.intervalMs ?? libraryModule.SYNC_INTERVAL_MS);
@@ -390,7 +425,10 @@ export async function startBroker({
       threadsState: (business) => broker.threadsState(business),
       threadIdle: (r) => broker.threadIdle(r),
       // Row 125 (#1619, REQ-LIMIT-4): the launcher asks the limit checks before every launch.
-      mayLaunch: ({ business, instance, provider, model, account = null }) => limits.mayLaunch(business, { instance, provider, model, account }),
+      mayLaunch: async ({ business, instance, provider, model, account = null }) => {
+        processingWork();
+        return limits.mayLaunch(business, { instance, provider, model, account });
+      },
       identity: (cap) => broker.identity(cap),
       authorizeLaunch,
       checkPush,
@@ -417,6 +455,7 @@ export async function startBroker({
         await stopSync();
         await server.close();
         await adapter?.close?.();
+        await processing?.close();
         store.close();
         credentials.close();
       },
@@ -424,6 +463,7 @@ export async function startBroker({
   } catch (e) {
     await server?.close();
     await adapter?.close?.();
+    await processing?.close();
     store?.close();
     credentials?.close();
     throw e;

packages/bus/src/server.mjs

@@ -134,8 +134,9 @@ export async function serve({ broker, path, authenticateHuman = null, authentica
             });
           return;
         }
-        // Row138: only project Git effects need an await; preserve every other sync path below.
-        if (r.verb === 'usage.begin' || r.verb === 'usage.end' ||
+        // Async effects retain the synchronous path for every other verb.
+        if (r.verb === 'processing.halt' || r.verb === 'processing.resume' ||
+            r.verb === 'usage.begin' || r.verb === 'usage.end' ||
             r.verb === 'spec.read' || r.verb === 'record.write' || PROJECT_FILE_VERBS.includes(r.verb) || LIBRARY_VERBS.includes(r.verb) ||
             // Row 234 (#1740): a grant raise awaits its keyscan, and hosts.check its ssh.
             HOSTS_VERBS.includes(r.verb) ||

packages/bus/src/web.mjs

@@ -11,6 +11,7 @@
 // every call and labels every reply untrusted (broker.mjs, requestWeb).
 
 import { SEARCH_MAX_QUERY_CHARS, WEB_DEFAULTS, WEB_REFUSAL, WebRefusal, webFetch } from "../../discord/src/web.mjs";
+import { currentProcessing } from '../../processing-control/src/effects.mjs';
 
 export const WEB_SEARCH_NOT_CONFIGURED = "search is not configured for this business";
 // Under the runner's own 30 s wait for a tool call, so a slow source is a refusal, not a lost reply.
@@ -28,6 +29,7 @@ export function webService({ search = null, maxFetchBytes = WEB_DEFAULTS.maxFetc
   // so a stalled backend is cut off, not just ignored: web.mjs destroys its request on abort, and a
   // search-source module gets the signal as the `signal` of its last argument.
   const within = (start) => {
+    const processing = currentProcessing(); processing?.guard();
     const controller = new AbortController();
     let timer;
     const late = new Promise((_, reject) => {
@@ -36,7 +38,8 @@ export function webService({ search = null, maxFetchBytes = WEB_DEFAULTS.maxFetc
         reject(new WebRefusal(WEB_REFUSAL.TIMEOUT));
       }, deadlineMs);
     });
-    return Promise.race([start(controller.signal), late]).finally(() => clearTimeout(timer));
+    const signal = processing ? AbortSignal.any([processing.signal, controller.signal]) : controller.signal;
+    return Promise.race([start(signal), late]).finally(() => clearTimeout(timer));
   };
   async function run(verb, args) {
     if (verb === "web.fetch") {

packages/bus/tests/processing-runtime.test.mjs

@@ -0,0 +1,65 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { mkdtempSync, rmSync, writeFileSync } from 'node:fs';
+import { join } from 'node:path';
+import { tmpdir } from 'node:os';
+import { spawn } from 'node:child_process';
+import { once } from 'node:events';
+import { startBroker } from '../src/runtime.mjs';
+import { Client } from '../src/client.mjs';
+import { registerRuntime, updateRuntime, processIdentity } from '../../processing-control/src/runtimes.mjs';
+import { readControl } from '../../processing-control/src/state.mjs';
+
+const businesses = { demo: { id: 'demo', human: 'jason', arbiters: { technical: 'coder', delivery: 'coder' },
+  roles: { coder: { authority: { withinRole: ['message.send'], crossRole: [] } } } } };
+async function broker(root) {
+  const r = await startBroker({ dataRoot: root, businesses, readers: ['demo'] });
+  const cap = r.broker.bindHuman({ business: 'demo', human: 'jason', via: 'cli', outsideAgent: true });
+  return { r, client: new Client({ path: r.path, cap, timeout: 15000 }) };
+}
+
+test('real runtime injects the coordinator, stops its workload and mirrors stable stop events across restart', async t => {
+  const root = mkdtempSync(join(tmpdir(), 'processing-runtime-bus-'));
+  let live;
+  const p = spawn(process.execPath, ['-e', "console.log('ready');setInterval(()=>{},1000)"], { detached: true, stdio: ['ignore', 'pipe', 'ignore'] });
+  const exit = once(p, 'exit');
+  t.after(async () => {
+    await live?.close();
+    if (p.exitCode === null && p.signalCode === null) { try { process.kill(-p.pid, 'SIGKILL'); } catch {} await exit; }
+    rmSync(root, { recursive: true, force: true });
+  });
+  await once(p.stdout, 'data');
+  let current = await broker(root); live = current.r;
+  const receipt = registerRuntime(root, { kind: 'session', business: 'demo', run: 'runtime-fixture' });
+  updateRuntime(root, receipt.id, { ...processIdentity(p.pid), phase: 'running', group: true });
+  const halted = await current.client.call('processing.halt');
+  assert.equal(halted.halted, true);
+  assert.equal(halted.quiescent, true);
+  await exit;
+  assert.equal(processIdentity(p.pid), null);
+  await assert.rejects(live.mayLaunch({ business: 'demo', instance: 'coder', provider: 'fixture', model: 'fixture' }), { code: 'processing-halted' });
+  await live.close(); live = null;
+  current = await broker(root); live = current.r;
+  assert.equal((await current.client.call('processing.status')).halted, true);
+  const events = [halted.generation, receipt.id].flatMap(subject =>
+    live.broker.request(live.readers[0].cap, { verb: 'trail', args: { subject } }));
+  assert.equal(events.filter(e => e.body?.action === 'processing.halt').length, 1);
+  assert.equal(events.filter(e => e.body?.action === 'processing.stop').length, 1);
+  assert.equal((await current.client.call('processing.resume', { generation: halted.generation })).halted, false);
+});
+
+test('invalid state still starts the control bus and human halt then resume repairs it', async t => {
+  const root = mkdtempSync(join(tmpdir(), 'processing-repair-bus-'));
+  let live;
+  t.after(async () => { await live?.close(); rmSync(root, { recursive: true, force: true }); });
+  let current = await broker(root); live = current.r;
+  await live.close(); live = null;
+  writeFileSync(join(root, 'control', 'processing.json'), '{');
+  current = await broker(root); live = current.r;
+  assert.equal((await current.client.call('processing.status')).code, 'processing-state-invalid');
+  await assert.rejects(current.client.call('processing.resume', { generation: 'bad' }), { code: 'processing-state-invalid' });
+  const halted = await current.client.call('processing.halt');
+  assert.equal(halted.recovered, true);
+  assert.equal((await current.client.call('processing.resume', { generation: halted.generation })).halted, false);
+  assert.equal(readControl(root).halted, false);
+});

packages/bus/tests/processing-timeout.test.mjs

@@ -0,0 +1,31 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { createServer } from 'node:net';
+import { mkdtempSync, rmSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { Client } from '../src/client.mjs';
+test('processing halt and resume extend only the socket timeout while ordinary status retains the explicit timeout', async t => {
+  const root = mkdtempSync(join(tmpdir(), 'processing-client-')), path = join(root, 'fixture.sock');
+  const seen = [], sockets = new Set();
+  const server = createServer(socket => {
+    sockets.add(socket); let buffer = '', timer;
+    socket.on('error', () => {});
+    socket.on('close', () => { sockets.delete(socket); clearTimeout(timer); });
+    socket.on('data', data => {
+      buffer += data;
+      if (!buffer.includes('\n')) return;
+      seen.push(JSON.parse(buffer));
+      timer = setTimeout(() => socket.end(JSON.stringify({ ok: true, result: { real: 'completion' } }) + '\n'), 80);
+    });
+  });
+  await new Promise(resolve => server.listen(path, resolve));
+  t.after(async () => { for (const socket of sockets) socket.destroy(); await new Promise(resolve => server.close(resolve)); rmSync(root, { recursive: true, force: true }); });
+  const client = new Client({ path, cap: 'a'.repeat(64), timeout: 15 });
+  for (const verb of ['processing.halt', 'processing.resume']) {
+    assert.deepEqual(await client.call(verb, {}), { real: 'completion' });
+    assert.equal(client.timeout, 15, 'the constructor setting stays unchanged');
+  }
+  await assert.rejects(client.call('processing.status'), { code: 'outcome-unknown' });
+  assert.deepEqual(seen, ['processing.halt', 'processing.resume', 'processing.status'].map(verb => ({ cap: 'a'.repeat(64), verb, args: {} })));
+});

packages/bus/tests/processing-web.test.mjs

@@ -0,0 +1,22 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { mkdtempSync, rmSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { initializeControl, transition } from '../../processing-control/src/state.mjs';
+import { withProcessing } from '../../processing-control/src/effects.mjs';
+import { webService } from '../src/web.mjs';
+test('a root halt aborts the active search-source signal before the normal web deadline', async t => {
+  const root = mkdtempSync(join(tmpdir(), 'processing-web-')); initializeControl(root);
+  t.after(() => rmSync(root, { recursive: true, force: true }));
+  let ready, observed;
+  const started = new Promise(resolve => { ready = resolve; });
+  const service = webService({ deadlineMs: 3000, search: { search: (_query, { signal }) => new Promise((_resolve, reject) => {
+    observed = signal; signal.addEventListener('abort', () => reject(signal.reason), { once: true }); ready();
+  }) } });
+  const call = withProcessing(root, () => service.handle('web.search', { query: 'fixture' }));
+  await started; const began = Date.now(); transition(root, { business: 'demo', human: 'jason', halted: true });
+  await call.catch(() => {});
+  assert.equal(observed.aborted, true); assert.equal(observed.reason.name, 'ProcessingError');
+  assert.ok(Date.now() - began < 1500);
+});

packages/bus/tests/processing.test.mjs

@@ -0,0 +1,143 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { mkdtempSync, rmSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { Broker } from '../src/broker.mjs';
+import { Store } from '../src/store.mjs';
+import { serve } from '../src/server.mjs';
+import { Client } from '../src/client.mjs';
+const state = await import('../../processing-control/src/state.mjs').catch(e => {
+  if (e.code === 'ERR_MODULE_NOT_FOUND') return {};
+  throw e;
+});
+const businesses = { demo: { id: 'demo', human: 'jason', vars: { 'bus.tester': true },
+  arbiters: { technical: 'coder', delivery: 'coder' }, roles: {
+    coder: { definition: 'coder', authority: { withinRole: ['message.send', 'record.write'], crossRole: [] } },
+  } } };
+function fixture(t, extra = {}) {
+  assert.equal(typeof state.initializeControl, 'function');
+  const root = mkdtempSync(join(tmpdir(), 'processing-bus-'));
+  state.initializeControl(root);
+  const store = new Store(root);
+  const processing = {
+    read: () => state.readControl(root),
+    async halt(actor) { return state.transition(root, { ...actor, halted: true }); },
+    async resume(actor) { return state.transition(root, { ...actor, halted: false }); },
+  };
+  const b = new Broker({ store, businesses, processing, ...extra });
+  const cap = b.bindLaunch({ business: 'demo', role: 'coder', run: 'run', harness: 'pi' });
+  b.request(cap, { verb: 'role.claim' });
+  const human = b.bindHuman({ business: 'demo', human: 'jason', via: 'cli', outsideAgent: true });
+  const reader = b.bindReader({ business: 'demo' });
+  const tester = b.bindTester({ business: 'demo' });
+  t.after(() => { store.close(); rmSync(root, { recursive: true, force: true }); });
+  return { root, b, store, cap, human, reader, tester, processing,
+    call: (who, verb, args = {}) => b.request(who, { verb, args }) };
+}
+
+// Dropping #human before either effect would allow a role/tester to clear the switch.
+for (const verb of ['processing.halt', 'processing.resume']) test(`${verb} refuses agent reader and tester before any transition`, async t => {
+  const f = fixture(t), before = state.readControl(f.root);
+  for (const cap of [f.cap, f.reader, f.tester]) {
+    await assert.rejects(async () => f.call(cap, verb, { generation: before.generation }), e => ['human-required', 'read-only', 'tester-refused'].includes(e.code));
+  }
+  assert.deepEqual(state.readControl(f.root), before);
+});
+
+test('human halt and clear each have one event with verified actor; launch.restore cannot clear', async t => {
+  const f = fixture(t);
+  const halted = await f.call(f.human, 'processing.halt');
+  assert.equal(halted.halted, true);
+  await f.call(f.human, 'processing.halt');
+  f.call(f.human, 'launch.restore');
+  assert.equal(f.call(f.reader, 'processing.status').halted, true);
+  const resumed = await f.call(f.human, 'processing.resume', { generation: halted.generation });
+  assert.equal(resumed.halted, false);
+  const events = f.store.all("SELECT body FROM events WHERE kind='action.allowed' AND json_extract(body,'$.action') IN ('processing.halt','processing.resume')").map(r => JSON.parse(r.body));
+  assert.deepEqual(events.map(e => [e.action, e.human]), [['processing.halt', 'jason'], ['processing.resume', 'jason']]);
+  assert.equal(new Set(events.map(e => e.operation)).size, 2);
+});
+
+test('all ordinary work verbs refuse before dispatch while pure reads remain available', async t => {
+  const f = fixture(t); await f.call(f.human, 'processing.halt');
+  for (const verb of ['role.claim', 'role.revoke', 'decision.raise', 'decision.resolve', 'message.send', 'message.receive', 'message.read', 'staff.request', 'review.request', 'review.verdict', 'event.emit', 'organization.set', 'record.write', 'usage.begin', 'unknown.future.work']) {
+    await assert.rejects(async () => f.call(f.cap, verb), { code: 'processing-halted' }, verb);
+  }
+  assert.equal(f.call(f.cap, 'state').launch.state, 'allowed');
+  assert.ok(Array.isArray(f.call(f.reader, 'agents')));
+  assert.equal(f.call(f.reader, 'processing.status').halted, true);
+  // A human can still queue intent and manage settings under their existing permissions.
+  assert.doesNotThrow(() => f.call(f.human, 'message.send', { to: 'coder', body: 'wait for resume' }));
+  assert.doesNotThrow(() => f.call(f.cap, 'role.release'));
+});
+
+test('task web authorization and bind paths refuse before external work', async t => {
+  const f = fixture(t); await f.call(f.human, 'processing.halt');
+  let effects = 0;
+  await assert.rejects(f.b.requestTask(f.cap, { verb: 'task.get', args: {} }, () => { effects++; }), { code: 'processing-halted' });
+  await assert.rejects(f.b.requestWeb(f.cap, { verb: 'web.fetch', args: { url: 'https://example.com' } }, { handle() { effects++; } }), { code: 'processing-halted' });
+  assert.throws(() => f.b.authorize(f.cap, 'role.launch', { target: 'coder' }), { code: 'processing-halted' });
+  assert.throws(() => f.b.bindLaunch({ business: 'demo', role: 'coder', run: 'later', harness: 'pi' }), { code: 'processing-halted' });
+  assert.equal(effects, 0);
+});
+
+for (const action of ['processing.halt', 'processing.resume', 'processing.stop']) test(`recordEvent cannot forge ${action}`, t => {
+  const f = fixture(t);
+  assert.throws(() => f.b.recordEvent(f.cap, { kind: 'action.allowed', body: { action, human: 'jason' } }), { code: 'reserved-event' });
+  assert.equal(f.store.get("SELECT count(*) n FROM events WHERE kind='action.allowed'").n, 0);
+});
+
+for (const own of [false, true]) test(`recordTask ${own ? 'self' : 'poll'} cannot forge a processing action through its kinds filter`, t => {
+  const f = fixture(t);
+  assert.throws(() => f.b.recordTask({ business: 'demo', ...(own ? { cap: f.cap } : {}), events: [
+    { kind: 'action.allowed', body: { action: 'processing.halt', human: 'jason' } },
+  ] }), { code: 'reserved-event' });
+});
+
+test('spec read remains a read but cannot release new write work after an await', async t => {
+  let finish;
+  const ready = new Promise(resolve => { finish = resolve; });
+  const f = fixture(t, { project: { async writeRecord() { await ready; return { path: 'docs/a.md', commit: 'a'.repeat(40) }; } } });
+  const writing = f.call(f.cap, 'record.write', { project: 'stack', path: 'docs/a.md', record: '# A' });
+  await f.call(f.human, 'processing.halt'); finish();
+  // An already committed external effect must remain outcome-unknown, not a fake rollback.
+  await assert.rejects(writing, { code: 'outcome-unknown' });
+});
+
+test('the real socket awaits halt and resume beyond the ordinary idle deadline', async t => {
+  const f = fixture(t), path = join(f.root, 'control.sock');
+  const halt = f.processing.halt;
+  f.processing.halt = async args => { await new Promise(r => setTimeout(r, 30)); return halt(args); };
+  let peers = 0;
+  const server = await serve({ broker: f.b, path, timeout: 5,
+    // Row 196 added asynchronous kernel-peer discovery before the dispatch timeout.
+    // This test isolates the post-auth await; peer proof is exercised in its owning files.
+    peerReader: { close: async () => {}, read: async () => { peers++; return { pid: process.pid, uid: process.getuid(), gid: process.getgid() }; } },
+    authenticateHuman: () => f.b.bindHuman({ business: 'demo', human: 'jason', via: 'cli', outsideAgent: true }) });
+  try {
+    const client = new Client({ path, human: { fixture: true }, timeout: 1000 });
+    const halted = await client.call('processing.halt');
+    assert.equal(halted.halted, true);
+    assert.equal((await client.call('processing.resume', { generation: halted.generation })).halted, false);
+    assert.equal((await new Client({ path, cap: f.reader }).call('processing.status')).halted, false);
+    assert.equal(peers, 2);
+  } finally { await server.close(); }
+});
+
+test('a malformed processing reader never silently admits agent work', t => {
+  const f = fixture(t);
+  for (const answer of [null, {}, { halted: false }, { version: 1, generation: 'bad', halted: false }, { halted: 'false' }]) {
+    f.processing.read = () => answer;
+    assert.throws(() => f.call(f.cap, 'message.send', { to: 'human', body: 'no' }), { code: 'processing-state-invalid' });
+  }
+});
+
+test('halt refuses the newly landed host executor path before credentials or effects', async t => {
+  const f = fixture(t); await f.call(f.human, 'processing.halt');
+  let called = false;
+  await assert.rejects(f.b.requestHost(f.cap, { verb: 'host.run', args: {} }, {
+    busy: () => { called = true; return false; }, run: async () => { called = true; },
+  }), e => e.code === 'processing-halted');
+  assert.equal(called, false);
+});

packages/bus/tests/project-runtime.test.mjs

@@ -15,7 +15,9 @@ test('Broker keeps the sandbox client import closure: only the listed imports, n
     // Row 210 (#1707): createHash gives host.run events the argv, stdin and output sha256 values.
     "import { randomUUID, randomBytes, createHash } from 'node:crypto';",
     // Row 65 (#1558): bindLaunch checks a run's transcript path is absolute.
-    "import { isAbsolute } from 'node:path';",
+    "import { isAbsolute, dirname } from 'node:path';",
+    // Row 191 / sage-1367: the one additional read-only CODE source, with no project/git imports.
+    "import { initializeControl, processingStatus } from '../../processing-control/src/state.mjs';",
     // Row 65: the plug-in name pattern a harness takes. kinds.mjs is in RUNNER_FILES and imports nothing.
     "import { NAME as HARNESS_NAME } from '../../plugins/src/kinds.mjs';",
     "import { loadRequirements } from '../../tasks/src/requirements.mjs';",

packages/bus/tests/tasks.test.mjs

@@ -249,16 +249,19 @@ test('the runtime refuses an invalid adapter and closes a valid one', async (t)
   // Each refusal closed what it had opened, the adapter included; the writer lock is free.
   assert.equal(closed, 4);
   assert.equal(existsSync(join(root, 'bus/writer.lock')), false);
-  let given = null;
+  let given = null, processing = null;
   const runtime = await startBroker({
     dataRoot: root,
     businesses,
     tasks: async (deps) => {
       given = Object.keys(deps).sort();
+      processing = deps.processing;
       return { handle: async () => ({ ok: 1 }), timeout: 1000, close: async () => closed++ };
     },
   });
-  assert.deepEqual(given, ['broker', 'businesses', 'credentials']);
+  // Row 191: runtime injects cancellation alongside the existing factory dependencies.
+  assert.deepEqual(given, ['broker', 'businesses', 'credentials', 'processing']);
+  assert.equal(typeof processing.work, 'function');
   await runtime.close();
   assert.equal(closed, 5);
   await assert.rejects(

packages/cli/README.md

@@ -1107,3 +1107,14 @@ The helper supplies the fixed logical origin, reports status/text/body as JSON,
 and never retries an uncertain write. It cannot navigate a browser or upgrade the
 tester to an owner. `mosaic ... --tester` continues using broker.sock directly.
 See docs/TOOLS.md for explicit activation conversion and rollback behavior.
+
+## Instance processing switch
+
+`mosaic halt [--business ID]` and `mosaic resume [--business ID]` use the human
+management path even when the CLI channel is disabled. The business chooses
+proof context; the affected scope is every managed workload in the resolved
+data root. Read `mosaic processing status --json` after an unknown or partial
+result. Resume refuses unconfirmed stops and a stale generation. A restarted
+`bus start --pm` keeps its control bus up while halted and skips the chief.
+The switch does not clear other launch/Discord brakes or retry tasks. Native
+diagnostic launch stays available. See packages/processing-control/README.md.

packages/cli/src/cli.mjs

@@ -59,6 +59,9 @@ export const USAGE = `usage:
   ${THREAD_TALK_USAGE}
   mosaic name <instance> <name> [--business <id>] [--tester]
   mosaic names [--business <id>] [--json] [--tester]
+  mosaic halt [--business <id>]
+  mosaic resume [--business <id>]
+  mosaic processing status [--business <id>] [--json]
   mosaic stop <run>
   mosaic launches off|on [--business <id>]
   mosaic launches list [--json]
@@ -458,6 +461,36 @@ async function stop(rest, io, deps) {
   io.stdout.write(r.stopped ? `stopped ${r.business}/${r.instance} run ${r.run}\n` : `${r.reason}\n`);
 }
 
+async function processingCommand(verb, rest, io, deps) {
+  const parsed = parse(rest, { flags: ["--json"], values: ["--business"] });
+  if (verb === 'processing' ? parsed.positional.length !== 1 || parsed.positional[0] !== 'status' : parsed.positional.length !== 0)
+    throw usage('use mosaic halt, mosaic resume or mosaic processing status');
+  refuseInsideAgent(io.env);
+  const system = deps.system ?? loadSystem({ env: io.env });
+  const call = callFor(parsed, io, { ...deps, system });
+  try {
+    let result;
+    if (verb === 'resume') {
+      const current = await call('processing.status');
+      if (current?.invalid) throw new CliError(`processing state is invalid; use mosaic halt, then mosaic resume (${current.code})`, 3);
+      result = await call('processing.resume', { generation: current?.generation });
+    } else result = await call(verb === 'halt' ? 'processing.halt' : 'processing.status', {});
+    if (!result || typeof result !== 'object' || (typeof result.halted !== 'boolean' && !result.invalid))
+      throw new CliError('processing outcome unknown; use mosaic processing status before trying again', 1);
+    if (verb === 'halt' && result.quiescent !== true)
+      throw new CliError(`halt gate is on for instance ${system.dataRoot}; ${result.remaining ?? 'unknown'} stops unconfirmed. Use mosaic processing status`, 1);
+    if (parsed.flags.has('--json')) { io.stdout.write(JSON.stringify(result, null, 2) + '\n'); return; }
+    const status = verb === 'resume' ? 'resumed' : result.halted ? 'halted' : result.invalid ? 'uninitialized' : 'running';
+    io.stdout.write(`processing ${status} for instance ${system.dataRoot}\n`);
+    if (result.invalid) io.stdout.write('state is invalid; use mosaic halt, then mosaic resume\n');
+  } catch (e) {
+    if (e instanceof CliError) throw e;
+    const code = typeof e.code === 'string' && /^[a-z-]{1,64}$/.test(e.code) ? e.code : 'outcome-unknown';
+    if (code === 'outcome-unknown') throw new CliError('processing outcome unknown; use mosaic processing status before trying again', 1);
+    throw new CliError(`processing refused: ${code}`, 3);
+  }
+}
+
 async function launches(rest, io, deps) {
   const [sub, ...args] = rest;
   if (sub === "off" || sub === "on") {
@@ -512,8 +545,13 @@ async function bus(rest, io, deps) {
       await launcher.listen();
       io.stdout.write(`bus host up: business ${businessId}, socket ${host.path}, notifier ${binding ?? "off"}${launches ? "" : ", launches disabled"}\n`);
       if (parsed.flags.has("--pm")) {
-        const pm = await launcher.launchPm();
-        io.stdout.write(`launched ${pm.instance}: run ${pm.run}, ${pm.harness} ${pm.model}\n`);
+        try {
+          const pm = await launcher.launchPm();
+          io.stdout.write(`launched ${pm.instance}: run ${pm.run}, ${pm.harness} ${pm.model}\n`);
+        } catch (e) {
+          if (e.code !== 'processing-halted') throw e;
+          io.stdout.write('processing halted: chief launch skipped; control bus remains available\n');
+        }
       }
     } catch (e) {
       await host.close(1);
@@ -600,6 +638,7 @@ export async function main(argv, io = { env: process.env, stdin: process.stdin,
   if (verb === "follow") return talk(rest, io, deps, true);
   if (verb === "name" || verb === "names") return names(verb, rest, io, deps);
   if (verb === "stop") return stop(rest, io, deps);
+  if (["halt", "resume", "processing"].includes(verb)) return processingCommand(verb, rest, io, deps);
   if (verb === "launches") return launches(rest, io, deps);
   if (verb === "bus") return bus(rest, io, deps);
   if (verb === "-h" || verb === "--help") return io.stdout.write(`${USAGE}\n`);

packages/cli/src/git-socket.mjs

@@ -85,6 +85,7 @@ import { gitSocketPath } from "../../seat/src/session.mjs";
 import { gateEnv, isMosaicStack, rootHits, runGate } from "../../seat/src/landing.mjs";
 import { BUNDLE_MAX, dropLand, finishLand, FSCK, HAVE_MAX, prepareLand, publish, push, review, validBranch, workRef, WorkingError } from "../../seat/src/working.mjs";
 import { CliError } from "./errors.mjs";
+import { withProcessing } from '../../processing-control/src/effects.mjs';
 
 const HEADER_MAX = 4096;
 const HEADER_TIMEOUT_MS = 10000;
@@ -372,7 +373,7 @@ export function createGitSocket({ host, business: b, dataRoot, env = process.env
     const p = project(facts.project);
     const where = { dataRoot, business: b.id, project: facts.project, env };
     const refused = async (e, notify) => {
-      const code = e instanceof Refusal || e instanceof Recorded || e instanceof WorkingError ? e.code : "git-failed";
+      const code = e instanceof Refusal || e instanceof Recorded || e instanceof WorkingError || e.name === 'ProcessingError' ? e.code : "git-failed";
       if (code === "git-failed" || code === "rollback-failed") log(`git socket: ${id}: ${code}: ${e.message}`);
       // The host's own faults stay in its log; the role gets the code.
       const detail = notify && code !== "git-failed" && e.message !== code ? e.message.slice(0, 1000) : null;
@@ -392,20 +393,19 @@ export function createGitSocket({ host, business: b, dataRoot, env = process.env
     }
     const { commit, base, reviewed, patch_id } = prepared;
     socket.end(`${JSON.stringify({ ok: true, result: { landing: "started", commit, base, reviewed, patch_id } })}\n`);
-    slot.done = (async () => {
+    slot.done = withProcessing(dataRoot, async scope => {
       try {
-        const r = await gate.run({ worktree: prepared.worktree, logs, env: gateEnv(env), signal: slot.abort.signal });
+        const r = await gate.run({ worktree: prepared.worktree, logs, env: gateEnv(env), signal: AbortSignal.any([slot.abort.signal, scope.signal]) });
+        scope.guard();
         if (r.aborted || slot.abort.signal.aborted) throw new Refusal("host-closing", "the host closed during the gate; nothing moved");
         if (!r.ok) throw new Refusal("gate-failed", `${r.step} failed, see ${r.log}`);
         await finishLand({ ...where, land: prepared, record: (m) => op({ op: "recordLand", ticket, land: { ...m, reviewed, base, patch_id } }) });
-      } catch (e) {
-        await refused(e, true);
       } finally {
         await dropLand({ ...where, worktree: prepared.worktree }).catch((x) => log(`git socket: ${id}: ${x.message}`));
         await gate.dropNetwork(`${id}_default`, gateEnv(env));
         landing = null;
       }
-    })();
+    }).catch(e => refused(e, true));
   }
 
   async function doPublish(socket, cap, req) {
@@ -479,11 +479,17 @@ export function createGitSocket({ host, business: b, dataRoot, env = process.env
       if (typeof req.task_ref === "string") subject = req.task_ref;
       if (!who.role || who.business !== b.id) throw new Refusal("not-a-role");
       file = join(dir, `${randomBytes(8).toString("hex")}.bundle`);
-      if (req.op === "push") await doPush(socket, cap, req, rest, file);
-      else if (req.op === "fetch") await doFetch(socket, cap, req, file);
-      else if (req.op === "land") await doLand(socket, cap, req);
-      else if (req.op === "publish") await doPublish(socket, cap, req);
-      else throw new Refusal("invalid-request", "op is push, fetch, land or publish");
+      await withProcessing(dataRoot, async scope => {
+        const abort = () => socket.destroy();
+        scope.signal.addEventListener('abort', abort, { once: true });
+        try {
+          if (req.op === "push") await doPush(socket, cap, req, rest, file);
+          else if (req.op === "fetch") await doFetch(socket, cap, req, file);
+          else if (req.op === "land") await doLand(socket, cap, req);
+          else if (req.op === "publish") await doPublish(socket, cap, req);
+          else throw new Refusal("invalid-request", "op is push, fetch, land or publish");
+        } finally { scope.signal.removeEventListener('abort', abort); }
+      });
     } catch (e) {
       if (e instanceof Recorded) return fail(e.code);
       const code = e instanceof Refusal || e instanceof WorkingError ? e.code : "git-failed";

packages/cli/src/launcher.mjs

@@ -127,6 +127,9 @@ import { createGitSocket } from "./git-socket.mjs";
 import { cmdlineOf, startTimeOf } from "../../seat/src/proc.mjs";
 import { rolesDir } from "./config.mjs";
 import { CliError } from "./errors.mjs";
+import { assertProcessing, processingStatus, ProcessingError } from "../../processing-control/src/state.mjs";
+import { registerRuntime, updateRuntime, runtime, unregisterRuntime, processIdentity } from "../../processing-control/src/runtimes.mjs";
+import { withProcessing } from '../../processing-control/src/effects.mjs';
 
 const STOP_TIMEOUT_MS = 30000;
 const LINE_MAX = 4096;
@@ -179,6 +182,13 @@ export function createLauncher({
   log = (l) => process.stderr.write(`mosaic-bus: ${l}\n`),
 }) {
   const dataRoot = system.dataRoot;
+  function admission(generation = null) {
+    try { return assertProcessing(dataRoot, generation); }
+    catch (e) {
+      if (e instanceof ProcessingError) throw new Refusal(e.code);
+      throw e;
+    }
+  }
   // Row 64 (#1557): where a role's skills are read from; scripts/skill.sh activate fills it.
   const skillsDir = join(dataRoot, "skills-enabled");
   let b = loadBusiness(host.business, { dir: configDir(env), rolesDir: rolesDir(env) });
@@ -231,6 +241,7 @@ export function createLauncher({
   // launch.by itself. A thread instance launches only for a thread, and
   // nothing else launches for one.
   async function check(instance, { pm = false, thread = null } = {}) {
+    const admissionGeneration = admission().generation;
     try { b=loadBusiness(host.business,{dir:configDir(env),rolesDir:rolesDir(env)}); } catch(e){throw new Refusal("organization-refused",e.message);}
     if (!b.launch) throw new Refusal("launch-not-configured", `business ${b.id} has no launch block`);
     if (!(pm ? instance === b.launch.by : b.launch.instances.includes(instance))) throw new Refusal("instance-not-listed");
@@ -324,11 +335,13 @@ export function createLauncher({
       if (may?.hit) { const error = new Refusal("limit-reached", JSON.stringify(may.hit)); error.limit = { check: may.check, ...may.hit }; throw error; }
       throw new Refusal("limit-check-failed", `${may?.check ?? "bus"}: ${may?.code ?? "malformed-answer"}`);
     }
-    return { resolved, model, account, harness, route, routeReason };
+    admission(admissionGeneration);
+    return { resolved, model, account, harness, route, routeReason, admissionGeneration };
   }
 
   // Bundle, spawn, bind, register, hand over the capability.
-  async function start({ instance, launchedBy, resolved, model, account = null, thread = null }) {
+  async function start({ instance, launchedBy, resolved, model, account = null, thread = null, admissionGeneration }) {
+    admission(admissionGeneration);
     // Every launch path ends here, so a --no-launch host spawns nothing whichever path asked.
     if (!launches) throw new Refusal("launches-disabled", "this host was started with --no-launch");
     // A thread's store is checked first, so a bad id or an unsafe directory
@@ -342,6 +355,7 @@ export function createLauncher({
       }
     }
     const credentials = await host.op({ op: "credentialStatus", business: b.id, role: instance });
+    admission(admissionGeneration);
     // The clones come before the run, so one that can't be made leaves no
     // run behind. The host's git treats each clone as hostile, and its
     // checks hold only while no session writes the workspace: a workspace
@@ -351,7 +365,10 @@ export function createLauncher({
     mkdirSync(workspace, { recursive: true, mode: 0o700 });
     let checkouts;
     try {
-      checkouts = await ensureCheckouts({ workspace, projects: Object.fromEntries(Object.entries(b.projects).filter(([, entry]) => entry.kind !== 'library')), env });
+      checkouts = await withProcessing(dataRoot, () => {
+        admission(admissionGeneration);
+        return ensureCheckouts({ workspace, projects: Object.fromEntries(Object.entries(b.projects).filter(([, entry]) => entry.kind !== 'library')), env });
+      });
     } catch (e) {
       if (e instanceof CheckoutError) throw new Refusal("checkout-failed", `${e.project}: ${e.message}`);
       throw e;
@@ -362,6 +379,7 @@ export function createLauncher({
     }
     let harness, route, routeReason;
     ({resolved,model,account,harness,route,routeReason}=await check(instance,{pm:instance===b.launch.by,thread}));
+    admission(admissionGeneration);
     const { run, runDir } = newRun(dataRoot, b.id);
     const sessionDir = store ? store.session : join(runDir, "session");
     if (!store) mkdirSync(sessionDir, { mode: 0o700 });
@@ -436,7 +454,16 @@ export function createLauncher({
       threadStore: store,
       readOnly,
     };
-    const child = spawnSession({ runDir, env: sessionEnv(env, run), paths, business: b.id, role: instance, bwrap });
+    admission(admissionGeneration);
+    const managed = registerRuntime(dataRoot, { kind: 'session', business: b.id, run });
+    let child;
+    try {
+      admission(admissionGeneration);
+      child = spawnSession({ runDir, env: sessionEnv(env, run), paths, business: b.id, role: instance, bwrap });
+    } catch (e) {
+      unregisterRuntime(dataRoot, managed.id);
+      throw e;
+    }
     let bound = false;
     let entry = null;
     const exited = new Promise((resolve) => child.once("close", (code, signal) => resolve(sessionExit(code, signal))));
@@ -445,10 +472,16 @@ export function createLauncher({
     try {
       if (child.pid === undefined) throw new Error("the session process did not start");
       const outerStart = startTimeOf(child.pid);
+      const identity = processIdentity(child.pid);
+      if (!identity) throw new Error("the session process exited at once");
+      updateRuntime(dataRoot, managed.id, { ...identity, group: true, phase: 'running' });
       const runner = await runnerOf(child);
+      updateRuntime(dataRoot, managed.id, { runnerPid: runner.pid, runnerStartTime: runner.startTime });
+      admission(admissionGeneration);
       if (!outerStart) throw new Error("the session process exited at once");
       const launch = await host.bindLaunch({ business: b.id, role: instance, run, harness: model.harness, provider: model.provider, model: model.model, account, transcript, pid: child.pid, startTime: outerStart, ...(thread ? { thread } : {}) });
       bound = true;
+      admission(admissionGeneration);
       entry = {
         business: b.id, instance, ...(thread ? { thread } : {}), run, launchedBy, harness: model.harness, model: model.model, provider: model.provider, modelKey: model.modelKey,
         pid: child.pid, startTime: outerStart, runnerPid: runner.pid, runnerStartTime: runner.startTime, runDir, startedAt: new Date().toISOString(),
@@ -462,20 +495,29 @@ export function createLauncher({
       child.kill("SIGKILL");
       await exited;
       if (bound) await endRun(run, "failed", null);
+      unregisterRuntime(dataRoot, managed.id);
+      if (e instanceof Refusal) throw e;
       throw new Refusal("launch-failed", e.message);
     }
     children.set(run, exited);
     exited.then(async ({ code, signal }) => {
-      const reason = endReason(code, signal);
+      let receipt;
+      try { receipt = runtime(dataRoot, managed.id); }
+      catch { log(`run ${run}: processing receipt unavailable at exit`); }
+      const state = processingStatus(dataRoot);
+      const haltGeneration = receipt?.haltGeneration ?? (state.halted && !state.invalid ? state.generation : null);
+      const reason = haltGeneration ? 'kill-switch' : endReason(code, signal);
       try {
         const ended = await endRun(run, reason, signal ? null : code);
         registry.remove(b.id, run);
         // Row 125 (#1619, REQ-LIMIT-4): a run a limit check stopped names the limit, from the claim row.
-        record({ event: "end", instance, ...(thread ? { thread } : {}), run, reason, exitCode: code, signal, ...(ended?.limit ? { limit: ended.limit } : {}) });
+        record({ event: "end", instance, ...(thread ? { thread } : {}), run, reason, exitCode: code, signal, ...(haltGeneration ? { haltGeneration } : {}), ...(ended?.limit ? { limit: ended.limit } : {}) });
         log(`run ${run} (${instance}) ended: ${reason}`);
       } catch (e) {
         log(`run ${run}: ${e.message}`);
       } finally {
+        try { unregisterRuntime(dataRoot, managed.id); }
+        catch { log(`run ${run}: processing receipt cleanup refused`); }
         children.delete(run);
         stopping.delete(run);
         landingOf.delete(run);
@@ -490,6 +532,7 @@ export function createLauncher({
   // landing pass. A tick that is still running when the next is due skips it.
   async function tick() {
     if (ticking || closed) return;
+    try { admission(); } catch { return; }
     ticking = true;
     try {
       await threadPass();
@@ -679,7 +722,9 @@ export function createLauncher({
       } catch (e) {
         if (!(e instanceof Refusal)) throw e;
         record({ event: "refused", by: b.human, instance: b.launch.by, code: e.code, why: e.message, ...(e.limit?{limit:e.limit}:{}) });
-        throw new CliError(`PM launch refused: ${e.code}${e.message !== e.code ? ` (${e.message})` : ""}`, 3);
+        const error = new CliError(`PM launch refused: ${e.code}${e.message !== e.code ? ` (${e.message})` : ""}`, 3);
+        error.code = e.code;
+        throw error;
       }
     });
   }

packages/cli/src/notifier-process.mjs

@@ -7,6 +7,7 @@
 import { Client } from "../../bus/src/client.mjs";
 import { openDirect } from "../../discord/src/notify.mjs";
 import { createNotifier, runLoop } from "./notifier.mjs";
+import { withProcessing, currentProcessing } from '../../processing-control/src/effects.mjs';
 
 const log = (line) => process.stderr.write(`mosaic-notify: ${line}\n`);
 let loop = null;
@@ -37,8 +38,13 @@ if (!process.send) {
     clearTimeout(timer);
     try {
       const client = new Client({ path: m.path, cap: m.cap });
-      const direct = openDirect({ dataRoot: m.dataRoot, name: m.binding, ...(m.base ? { base: m.base } : {}), log });
-      const notifier = createNotifier({ business: m.business, dataRoot: m.dataRoot, inbox: () => client.call("inbox"), direct, log });
+      const processing = { work: fn => withProcessing(m.dataRoot, fn), guard: () => currentProcessing()?.guard() };
+      const direct = openDirect({ dataRoot: m.dataRoot, name: m.binding, ...(m.base ? { base: m.base } : {}),
+        fetch: (url, init) => {
+          const scope = currentProcessing(); scope?.guard();
+          return fetch(url, { ...init, ...(scope ? { signal: scope.signal } : {}) });
+        }, log });
+      const notifier = createNotifier({ business: m.business, dataRoot: m.dataRoot, inbox: () => client.call("inbox"), direct, processing, log });
       loop = runLoop(notifier, { pollMs: m.pollMs ?? undefined, log });
       process.send({ ok: true });
     } catch (e) {

packages/cli/src/notifier.mjs

@@ -251,7 +251,7 @@ export function openJournal(file, { log = () => {}, now = () => new Date() } = {
 
 // inbox(): the broker's inbox through the reader capability.
 // direct.send({content, nonce}) resolves {messageId} or throws a RestOutcome.
-export function createNotifier({ business, dataRoot, inbox, direct, now = () => new Date(), zone = ZONE, log = () => {} }) {
+export function createNotifier({ business, dataRoot, inbox, direct, now = () => new Date(), zone = ZONE, processing = null, log = () => {} }) {
   zoned(now(), zone);
   const journal = openJournal(journalPath(dataRoot, business), { log, now });
   const backoff = new Map();
@@ -269,6 +269,7 @@ export function createNotifier({ business, dataRoot, inbox, direct, now = () =>
   }
 
   async function attempt(key, record, message) {
+    processing?.guard();
     const t = now().getTime();
     try {
       const { messageId } = await direct.send(message);
@@ -328,7 +329,11 @@ export function createNotifier({ business, dataRoot, inbox, direct, now = () =>
     return done;
   }
 
-  return Object.freeze({ tick, journal: journalPath(dataRoot, business) });
+  const poll = () => processing ? processing.work(tick).catch(e => {
+    if (e.name !== 'ProcessingError') throw e;
+    return { dms: 0, digest: false, failed: 0, halted: true };
+  }) : tick();
+  return Object.freeze({ tick: poll, journal: journalPath(dataRoot, business) });
 }
 
 // Runs tick() every pollMs until stop(). Ticks never overlap.

packages/cli/tests/host.test.mjs

@@ -1027,3 +1027,22 @@ test("bus-service.sh refuses a default claude without the execute bit, or in a P
   assert.ok(r.stderr.includes(join(spaced, "claude")), r.stderr);
   assert.equal(r.stdout, "");
 });
+
+// Row 191: a restarted halted instance must keep its recovery bus reachable.
+test('bus start --pm while halted keeps the control host up without launching the chief', { timeout: 30000 }, async t => {
+  const { initializeControl, transition, readControl } = await import('../../processing-control/src/state.mjs');
+  const f = fixture(tmp(t)); notifyConfig(f.dataRoot, 'acme', null);
+  initializeControl(f.dataRoot);
+  transition(f.dataRoot, { business: 'acme', human: 'jason', halted: true });
+  const child = spawn(process.execPath, [CLI, 'bus', 'start', 'acme', '--pm'], { env: f.env, stdio: ['ignore', 'pipe', 'pipe'] });
+  const exited = once(child, 'exit'); let output = '';
+  child.stdout.on('data', b => { output += b; }); child.stderr.on('data', b => { output += b; });
+  t.after(async () => { if (child.exitCode === null && child.signalCode === null) { child.kill('SIGTERM'); await exited; } });
+  await until(() => /processing halted: chief launch skipped/.test(output) || child.exitCode !== null);
+  assert.match(output, /processing halted: chief launch skipped/);
+  assert.equal(child.exitCode, null, output);
+  const status = spawnSync(process.execPath, [CLI, 'bus', 'status', '--json'], { env: f.env, encoding: 'utf8', timeout: 5000 });
+  assert.equal(status.status, 0, status.stderr);
+  assert.equal(JSON.parse(status.stdout).host.live, true);
+  assert.equal(readControl(f.dataRoot).halted, true);
+});

packages/cli/tests/launcher.test.mjs

@@ -1075,3 +1075,49 @@ test("a runner that ignores SIGTERM is killed when the host closes", { skip, tim
   assert.equal(ends.length, 1);
   assert.equal(ends[0].signal, "SIGKILL");
 });
+
+// Row 191: root-scoped processing is stronger than per-business launch.restore.
+test('kill switch refuses chief and hire before launch work and a clear permits a later request', { skip, timeout: 30000 }, async t => {
+  const { readControl, transition } = await import('../../processing-control/src/state.mjs');
+  const s = await setup(t);
+  const halted = transition(s.f.dataRoot, { business: 'acme', human: s.f.doc.human, halted: true });
+  await assert.rejects(s.launcher.launchPm(), /PM launch refused: processing-halted/);
+  assert.deepEqual(await s.launcher.fromSession(s.cto.cap, 'coder'), { ok: false, error: 'processing-halted' });
+  assert.deepEqual(readSessions(s.f.dataRoot), []);
+  transition(s.f.dataRoot, { business: 'acme', human: s.f.doc.human, halted: false, generation: halted.generation });
+  const run = await s.launcher.launchPm();
+  assert.equal(readControl(s.f.dataRoot).halted, false);
+  assert.equal(readSessions(s.f.dataRoot)[0].run, run.run);
+});
+
+test('kill switch stops an actual managed namespace and records the halt reason without rewriting its bundle', { skip, timeout: 30000 }, async t => {
+  const { transition } = await import('../../processing-control/src/state.mjs');
+  const s = await setup(t);
+  const run = await s.launcher.launchPm();
+  const entry = readSessions(s.f.dataRoot).find(r => r.run === run.run);
+  const session = readFileSync(join(entry.runDir, 'session.json'));
+  const halted = transition(s.f.dataRoot, { business: 'acme', human: s.f.doc.human, halted: true });
+  await until(() => !readSessions(s.f.dataRoot).some(r => r.run === run.run), 12000);
+  assert.deepEqual(readFileSync(join(entry.runDir, 'session.json')), session);
+  const end = log(s.f).find(r => r.event === 'end' && r.run === run.run);
+  assert.equal(end.reason, 'kill-switch');
+  assert.equal(end.haltGeneration, halted.generation);
+  assert.equal(startTimeOf(entry.runnerPid), null);
+});
+
+test('a launch waiting across halt and resume cannot use its stale admission', { skip, timeout: 30000 }, async t => {
+  const { transition } = await import('../../processing-control/src/state.mjs');
+  let root, first = true;
+  const prepared = prepare(t); root = prepared.f.dataRoot;
+  const s = await setup(t, doc => doc, prepared, { wrap: host => ({ ...host, async op(m) {
+    const answer = await host.op(m);
+    if (m.op === 'mayLaunch' && first) {
+      first = false;
+      const state = transition(root, { business: 'acme', human: 'jason', halted: true });
+      transition(root, { business: 'acme', human: 'jason', halted: false, generation: state.generation });
+    }
+    return answer;
+  } }) });
+  await assert.rejects(s.launcher.launchPm(), /processing-generation-changed/);
+  assert.deepEqual(readSessions(root), []);
+});

packages/cli/tests/notifier.test.mjs

@@ -451,3 +451,21 @@ test("runLoop never overlaps ticks and stops after the one in flight", async ()
   assert.ok(after >= 2);
   assert.equal(count, after);
 });
+
+// Row 191: the child remains alive for recovery but sends no processing while halted.
+test('processing halt prevents notifier reads and sends and fences the wait before delivery', async t => {
+  const { initializeControl, transition } = await import('../../processing-control/src/state.mjs');
+  const { createProcessing } = await import('../../processing-control/src/coordinator.mjs');
+  const dataRoot = tmp(t); initializeControl(dataRoot);
+  const bus = broker(t);
+  bus.raise('git.push.protected', { target: 'refactor', blocking: true, task_ref: 'vikunja:1/7' });
+  const processing = createProcessing({ dataRoot }); t.after(() => processing.close());
+  const actor = { business: 'demo', human: 'jason' }; let reads = 0, sends = 0, haltInRead = false;
+  const notifier = createNotifier({ business: 'demo', dataRoot, processing, now: () => new Date(AT),
+    inbox: async () => { reads++; if (haltInRead) transition(dataRoot, { ...actor, halted: true }); return bus.read('inbox'); },
+    direct: { send: async () => { sends++; return { messageId: 'fixture' }; } } });
+  const halted = transition(dataRoot, { ...actor, halted: true });
+  await notifier.tick(); assert.equal(reads, 0); assert.equal(sends, 0);
+  transition(dataRoot, { ...actor, halted: false, generation: halted.generation }); haltInRead = true;
+  await notifier.tick(); assert.equal(reads, 1); assert.equal(sends, 0);
+});

packages/cli/tests/processing-cli.test.mjs

@@ -0,0 +1,55 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { mkdtempSync, rmSync } from 'node:fs';
+import { join } from 'node:path';
+import { tmpdir } from 'node:os';
+import { Store } from '../../bus/src/store.mjs';
+import { Broker } from '../../bus/src/broker.mjs';
+import { createProcessing } from '../../processing-control/src/coordinator.mjs';
+import { main } from '../src/cli.mjs';
+import { io, BUSINESSES } from './helpers.mjs';
+function setup(t) {
+  const dataRoot = mkdtempSync(join(tmpdir(), 'processing-cli-')), calls = [];
+  const processing = createProcessing({ dataRoot });
+  const store = new Store(dataRoot);
+  const b = new Broker({ store, businesses: BUSINESSES, processing });
+  const human = b.bindHuman({ business: 'demo', human: 'jason', via: 'cli', outsideAgent: true });
+  const deps = { system: { dataRoot }, transport: business => async (verb, args = {}) => {
+    assert.equal(business, 'demo'); calls.push(verb); return b.request(human, { verb, args });
+  } };
+  t.after(async () => { await processing.close(); store.close(); rmSync(dataRoot, { recursive: true, force: true }); });
+  return { dataRoot, deps, calls };
+}
+
+test('human halt/status/resume uses management transport without loading any channel', async t => {
+  const f = setup(t), x = io();
+  await main(['halt', '--business', 'demo'], x, f.deps);
+  assert.match(x.out.text, /processing halted/);
+  assert.ok(x.out.text.includes(f.dataRoot), 'the affected instance root is named');
+  const status = io();
+  await main(['processing', 'status', '--business', 'demo', '--json'], status, f.deps);
+  assert.equal(JSON.parse(status.out.text).halted, true);
+  const resumed = io(); await main(['resume', '--business', 'demo'], resumed, f.deps);
+  assert.match(resumed.out.text, /processing resumed/);
+  assert.deepEqual(f.calls, ['processing.halt', 'processing.status', 'processing.status', 'processing.resume']);
+});
+
+for (const verb of ['halt', 'resume']) test(`${verb} refuses inside an agent before transport`, async t => {
+  const f = setup(t), x = io({ MOSAIC_RUN_ID: 'managed-run' });
+  await assert.rejects(main([verb, '--business', 'demo'], x, f.deps), e => e.exitCode === 3);
+  assert.deepEqual(f.calls, []);
+});
+
+test('unknown and partially stopped outcomes are never reported as a successful halt', async t => {
+  const f = setup(t);
+  const unknown = io();
+  await assert.rejects(main(['halt', '--business', 'demo'], unknown, {
+    ...f.deps, transport: () => async () => { throw Object.assign(new Error('outcome-unknown'), { code: 'outcome-unknown' }); },
+  }), e => e.exitCode === 1 && /status/.test(e.message));
+  assert.doesNotMatch(unknown.out.text, /processing halted/);
+  const partial = io();
+  await assert.rejects(main(['halt', '--business', 'demo'], partial, {
+    ...f.deps, transport: () => async () => ({ version: 1, generation: '11111111-1111-4111-8111-111111111111', operation: '11111111-1111-4111-8111-111111111111', business: 'demo', human: 'jason', at: '2026-10-20T00:00:00.000Z', recovered: false, halted: true, quiescent: false, remaining: 1, stopped: 0 }),
+  }), e => e.exitCode === 1 && /1.*unconfirmed/.test(e.message));
+  assert.doesNotMatch(partial.out.text, /all.*stopped/);
+});

packages/cli/tests/stack-copy.test.mjs

@@ -49,7 +49,7 @@ test('a copy carries every file the harness modules read from it',async t=>{
 test('shared copy: npm ci, pushed reachability, readonly/existing copy, webui delegation',t=>{
  const s=setup(t),r=s.run('stack-copy.sh',['copy',s.id,'--copies',s.copies]);assert.equal(r.status,0,r.stderr);
  const copy=join(s.copies,s.id);assert.equal(statSync(copy).mode&0o777,0o555);
- for(const f of ['scripts/mosaic','adapters/pi/adapter.sh','packages/queue/src/cli.mjs','package.json','package-lock.json','packages/tasks/requirements.json','packages/project/src/index.mjs','packages/library/src/index.mjs','packages/project/schemas/project.schema.json','packages/project/templates/north-star.md','packages/plugins/src/kinds.mjs','packages/plugins/src/loader.mjs'])assert.ok(existsSync(join(copy,f)),f);
+ for(const f of ['scripts/mosaic','adapters/pi/adapter.sh','packages/queue/src/cli.mjs','package.json','package-lock.json','packages/tasks/requirements.json','packages/project/src/index.mjs','packages/library/src/index.mjs','packages/project/schemas/project.schema.json','packages/project/templates/north-star.md','packages/plugins/src/kinds.mjs','packages/plugins/src/loader.mjs','packages/processing-control/src/state.mjs','packages/processing-control/src/containers.mjs','packages/processing-control/src/effects.mjs'])assert.ok(existsSync(join(copy,f)),f);
  const npm=join(s.bin,'npm');writeFileSync(npm,'#!/bin/sh\nexit 99\n');chmodSync(npm,0o755);
  const existing=s.run('webui-service.sh',['copy',s.id,'--copies',s.copies]);assert.equal(existing.status,0);assert.equal(existing.stdout,`exists: ${copy}\n`);unlinkSync(npm);
  git(s.repo,'update-ref','refs/remotes/origin/refactor',git(s.repo,'hash-object','-w','package.json'));

packages/discord/src/cli.mjs

@@ -50,6 +50,8 @@ import { existsSync, mkdirSync, mkdtempSync, writeFileSync, statSync, readdirSyn
 import { join, resolve } from "node:path";
 import { createHash } from "node:crypto";
 import { DiscordError } from "./errors.mjs";
+import { assertProcessing, processingStatus, ProcessingError } from "../../processing-control/src/state.mjs";
+import { registerRuntime, updateRuntime, unregisterRuntime, processIdentity } from "../../processing-control/src/runtimes.mjs";
 import { defaultConfigPath, loadDataRoot, bindingPath, bindingDataDir, loadBinding, readToken, resolveContextFiles, resolveToolRoots, reloadDiff } from "./binding.mjs";
 import { createRest } from "./rest.mjs";
 import { createGateway, CONNECTOR_INTENTS } from "./gateway.mjs";
@@ -58,7 +60,7 @@ import { TOOLS_ENV, enabledToolNames } from "./tools.mjs";
 import { createSetsparkApi } from "./setspark.mjs";
 import { assembleContext } from "./context.mjs";
 import { createConnector } from "./connector.mjs";
-import { ensureJournal, requestStop, stopRequested, readPid, stopTarget, writePid, clearPid, unlock, recover, appendReload, BRAKE_EXIT } from "./journal.mjs";
+import { ensureJournal, requestStop, requestProcessingStop, stopRequested, readPid, stopTarget, writePid, clearPid, unlock, recover, appendReload, BRAKE_EXIT } from "./journal.mjs";
 
 const USAGE = [
   "usage: mosaic-discord check <binding> [--config PATH] [--repo PATH] [--offline]",
@@ -171,6 +173,9 @@ async function check(opts) {
 }
 
 async function run(opts) {
+  const root = loadDataRoot(opts.config);
+  const generation = assertProcessing(root).generation;
+  const processing = () => assertProcessing(root, generation);
   const { bindingFile, binding, contextFiles, toolRoots, pi, journalDir, sessionDir } = prepare(opts);
   const token = readToken(binding);
   ensureJournal(journalDir);
@@ -180,8 +185,18 @@ async function run(opts) {
   }
   if (stopRequested(journalDir)) throw new DiscordError(`STOP is present in ${journalDir}; remove it to run`, BRAKE_EXIT);
   writePid(journalDir, process.pid);
-  const cleanupPid = () => clearPid(journalDir, process.pid);
+  let managed = null;
+  const cleanupPid = () => {
+    clearPid(journalDir, process.pid);
+    if (!managed) return;
+    if (processingStatus(root).halted) updateRuntime(root, managed.id, { phase: 'ended' });
+    else unregisterRuntime(root, managed.id);
+  };
   try {
+    processing();
+    managed = registerRuntime(root, { kind: 'discord', business: 'instance', run: binding.name });
+    updateRuntime(root, managed.id, { ...processIdentity(process.pid), phase: 'running', group: false });
+    processing();
     await runClaimed();
   } catch (err) {
     cleanupPid();
@@ -201,6 +216,7 @@ async function run(opts) {
 
     const rest = createRest({ token, log: warn });
     const gw = await rest.getGatewayBot();
+    processing();
     const gateway = createGateway({ url: gw.url, token, intents: CONNECTOR_INTENTS });
     gateway.on("log", (m) => warn(`gateway: ${m}`));
     gateway.on("ready", (r) => warn(`gateway: READY as ${r.user && r.user.id}, session ${r.sessionId}`));
@@ -208,6 +224,7 @@ async function run(opts) {
     gateway.on("closed", (c) => warn(`gateway: closed ${c.code} ${c.reason} reconnect=${c.willReconnect}`));
 
     const engine = createEngine({
+      processingRoot: root, binding: binding.name,
       command: pi,
       args: buildPiArgs({ ...binding.engine, sessionDir, appendSystemPromptFile: promptFile, continueSession, tools: toolRoots }),
       cwd: opts.repo,
@@ -223,15 +240,17 @@ async function run(opts) {
     // key as the model's verbs; without a setspark key it has none, and an
     // approval request from the model is refused.
     const api = binding.tools && binding.tools.setspark ? createSetsparkApi(binding.tools.setspark) : null;
-    const connector = createConnector({ binding, journalDir, rest, gateway, engine, api, log: warn });
+    const connector = createConnector({ binding, journalDir, rest, gateway, engine, api, processing, log: warn });
     let shuttingDown = false;
     let exitCode = 0;
-    const shutdown = (code) => {
+    let processingWatch = null;
+    const shutdown = (code, immediate = false) => {
       if (shuttingDown) return;
       shuttingDown = true;
+      clearInterval(processingWatch);
       exitCode = code;
-      warn("stopping: finishing in-flight turns");
-      connector.stop().catch((err) => warn(`stop failed: ${err.message}`)).finally(() => {
+      warn(immediate ? 'stopping: processing halted' : "stopping: finishing in-flight turns");
+      connector.stop({ immediate }).catch((err) => warn(`stop failed: ${err.message}`)).finally(() => {
         cleanupPid();
         process.exit(exitCode);
       });
@@ -240,8 +259,20 @@ async function run(opts) {
       warn(`gateway fatal close ${f.code}: ${f.reason}`);
       shutdown(2);
     });
-    process.on("SIGTERM", () => shutdown(0));
+    process.on("SIGTERM", () => shutdown(0, processingStatus(root).halted === true));
     process.on("SIGINT", () => shutdown(0));
+    processingWatch = setInterval(() => {
+      try { processing(); }
+      catch {
+        const state = processingStatus(root);
+        if (state.halted && !state.invalid) {
+          try { requestProcessingStop(journalDir, state.generation); }
+          catch { warn('processing STOP could not be recorded'); }
+        }
+        shutdown(BRAKE_EXIT, true);
+      }
+    }, 100);
+    processingWatch.unref();
 
     // Reload on SIGHUP: re-read the file, refuse anything that is not a
     // reloadable difference, verify new channels over REST, then swap.
@@ -250,11 +281,13 @@ async function run(opts) {
     const reloadNow = async () => {
       const at = new Date().toISOString();
       try {
+        processing();
         const next = loadBinding(bindingFile);
         if (next.name !== binding.name) throw new DiscordError(`reload: name ${JSON.stringify(next.name)} does not match ${binding.name}`);
         const diff = reloadDiff(connector.binding, next);
         for (const id of diff.channels.added) {
           const ch = await rest.getChannel(id);
+          processing();
           if (ch.guild_id !== next.guildId) throw new DiscordError(`reload: channel ${id} is in guild ${ch.guild_id}, not ${next.guildId}`);
         }
         connector.reload(next);
@@ -330,6 +363,7 @@ function reloadCommand(opts) {
 
 function recoverCommand(opts) {
   const dataRoot = loadDataRoot(opts.config);
+  assertProcessing(dataRoot);
   const binding = loadBinding(bindingPath(dataRoot, opts.binding));
   const journalDir = bindingDataDir(dataRoot, binding.name);
   ensureJournal(journalDir);
@@ -356,7 +390,7 @@ async function main() {
 main().then((code) => {
   if (code !== null) process.exit(code);
 }).catch((err) => {
-  const code = err instanceof DiscordError ? err.exitCode : 1;
+  const code = err instanceof ProcessingError ? BRAKE_EXIT : err instanceof DiscordError ? err.exitCode : 1;
   warn(err.message);
   if (err.details && err.details.nonces) warn(`nonces: ${err.details.nonces.join(", ")}`);
   process.exit(code);

packages/discord/src/connector.mjs

@@ -66,6 +66,7 @@ export function createConnector({
   setTimeoutImpl = globalThis.setTimeout, clearTimeoutImpl = globalThis.clearTimeout,
   typingIntervalMs = 8000,
   readReceipt = READ_RECEIPT,
+  processing = () => {},
   log = () => {},
 } = {}) {
   for (const [k, v] of Object.entries({ binding: initialBinding, journalDir, rest, gateway, engine })) {
@@ -73,6 +74,22 @@ export function createConnector({
   }
   ensureJournal(journalDir);
   let binding = initialBinding;
+  const guarded = object => new Proxy(object, {
+    get(target, key) {
+      const value = Reflect.get(target, key);
+      if (typeof value !== 'function') return value;
+      return (...args) => { processing(); return value.apply(target, args); };
+    },
+  });
+  rest = guarded(rest);
+  if (api) api = guarded(api);
+  function processingRefusal() {
+    try { processing(); return null; }
+    catch (e) {
+      if (e.code?.startsWith('processing-')) return e.code;
+      throw e;
+    }
+  }
 
   const state = {
     inbox: new Set(), channels: new Map(), inFlight: 0, typingTimer: null, typingChannel: null,
@@ -140,6 +157,7 @@ export function createConnector({
 
   function typingTick() {
     state.typingTimer = null;
+    if (processingRefusal()) return;
     if (state.inFlight === 0 || state.typingChannel === null) return;
     rest.typing(state.typingChannel);
     state.typingTimer = setTimeoutImpl(typingTick, typingIntervalMs);
@@ -287,6 +305,8 @@ export function createConnector({
   // is answered at once with a private line; an approval is deferred, the
   // service is asked, and the request message is then edited in place.
   async function handleInteraction(interaction) {
+    const refusal = processingRefusal();
+    if (refusal) return { accepted: false, reason: refusal };
     if (!interaction || typeof interaction !== "object" || typeof interaction.id !== "string") return { accepted: false, reason: "not-an-interaction" };
     if (interaction.type !== INTERACTION_TYPE.MESSAGE_COMPONENT) return { accepted: false, reason: "not-a-component" };
     if (state.interactions.has(interaction.id)) return { accepted: false, reason: "duplicate" };
@@ -383,6 +403,7 @@ ${status === "not-posted" ? APPROVAL_LINES.pressAgain : APPROVAL_LINES.failed}`;
       record.engine.turns = result.turns ?? null;
       if (binding.tools) record.tools = result.tools || [];
       if (result.model) record.engine.model = result.model;
+      processing();
       if (result.text.length === 0) throw new DiscordError("engine returned no text", 1, { code: "engine-empty" });
       reply = await deliver({ channelId: targetChannel, replyTo: message.id, text: result.text, noncePrefix: message.id });
       const opened = (result.tools || []).filter((t) => t && t.name === "open_approval_request" && t.ok && t.request);
@@ -392,10 +413,12 @@ ${status === "not-posted" ? APPROVAL_LINES.pressAgain : APPROVAL_LINES.failed}`;
       }
     } catch (err) {
       status = "failed";
-      error = { code: (err.details && err.details.code) || "error", message: err.message };
+      error = { code: err.code || (err.details && err.details.code) || "error", message: err.message };
       log(`turn ${message.id} failed: ${error.code}: ${error.message}`);
       // Q19: one fixed line, never model output, on failure.
-      reply = await deliver({ channelId: targetChannel, replyTo: message.id, text: FIXED_LINES.failed, noncePrefix: `${message.id}-f` });
+      if (!processingRefusal()) {
+        reply = await deliver({ channelId: targetChannel, replyTo: message.id, text: FIXED_LINES.failed, noncePrefix: `${message.id}-f` });
+      }
     } finally {
       state.inFlight -= 1;
       typingStop();
@@ -436,6 +459,8 @@ ${status === "not-posted" ? APPROVAL_LINES.pressAgain : APPROVAL_LINES.failed}`;
   }
 
   async function admit(message) {
+    const refusal = processingRefusal();
+    if (refusal) return drop(message, refusal);
     // A thread the connector has not seen: one REST lookup, only when the
     // cheap checks (guild, listed author) would let the message through.
     const listed = binding.channels.some((c) => c.id === message.channel_id);
@@ -447,6 +472,8 @@ ${status === "not-posted" ? APPROVAL_LINES.pressAgain : APPROVAL_LINES.failed}`;
         log(`channel lookup ${message.channel_id} failed: ${err.message}`);
       }
     }
+    const afterLookup = processingRefusal();
+    if (afterLookup) return drop(message, afterLookup);
     const auth = authorize(binding, message, channelInfo);
     if (!auth.ok) return drop(message, auth.reason);
     if (typeof message.content !== "string") return drop(message, "no-content");
@@ -567,10 +594,12 @@ ${status === "not-posted" ? APPROVAL_LINES.pressAgain : APPROVAL_LINES.failed}`;
     },
 
     async start() {
+      processing();
       if (state.started) throw new DiscordError("connector already started", 1);
       if (stopRequested(journalDir)) throw new DiscordError(`STOP is present in ${journalDir}; remove it to run`, 1);
       const reconciled = await reconcile();
       const approvals = await reconcileApprovals();
+      processing();
       if (approvals.length > 0) log(`approvals: ${approvals.map((a) => `${a.kind} ${a.requestId} ${a.status}`).join("; ")}`);
       state.inbox = readInboxIds(journalDir);
       state.started = true;
@@ -582,13 +611,14 @@ ${status === "not-posted" ? APPROVAL_LINES.pressAgain : APPROVAL_LINES.failed}`;
     },
 
     // Finish in-flight turns (each has its own timeout), then close.
-    async stop() {
+    async stop({ immediate = false } = {}) {
       state.stopping = true;
       gateway.close(1000, "stop");
+      if (immediate) await engine.stop();
       await Promise.allSettled([...state.turnPromises]);
       await state.deliveryChain;
       typingStop();
-      await engine.stop();
+      if (!immediate) await engine.stop();
     },
   };
 }

packages/discord/src/engine-pi.mjs

@@ -35,6 +35,8 @@ import { spawn as nodeSpawn } from "node:child_process";
 import { fileURLToPath } from "node:url";
 import { DiscordError } from "./errors.mjs";
 import { enabledToolNames } from "./tools.mjs";
+import { assertProcessing, processingStatus } from "../../processing-control/src/state.mjs";
+import { registerRuntime, updateRuntime, unregisterRuntime, processIdentity, runtime, runtimeGroupState, createRuntimeSignaller } from "../../processing-control/src/runtimes.mjs";
 
 export const PI_FIXED_ARGS = Object.freeze([
   "--mode", "rpc", "--no-extensions", "--no-context-files", "--no-skills",
@@ -81,6 +83,7 @@ export function createEngine({
   log = () => {},
   onExit = () => {},
   abortGraceMs = ABORT_GRACE_MS,
+  processingRoot = null, binding = null,
 } = {}) {
   if (typeof command !== "string" || command.length === 0) throw new DiscordError("engine: command required", 1);
   if (!Array.isArray(args)) throw new DiscordError("engine: args required", 1);
@@ -90,6 +93,18 @@ export function createEngine({
   // wedged: set when the engine gave up on pi and is stopping it. Nothing
   // is sent to that child again.
   const state = { child: null, buffer: "", pending: [], held: [], responses: new Map(), nextId: 1, busy: false, exited: null, wedged: false };
+  let managed = null;
+  const processing = () => {
+    if (processingRoot) return assertProcessing(processingRoot, managed?.generation ?? null);
+  };
+  const releaseRuntime = () => {
+    if (!managed) return;
+    try {
+      if (!processingStatus(processingRoot).halted && runtimeGroupState(runtime(processingRoot, managed.id)) === false)
+        unregisterRuntime(processingRoot, managed.id);
+    }
+    catch { log('engine: processing receipt cleanup refused'); }
+  };
 
   // A turn that fails on the client side (timeout, protocol error) stays in
   // the pending queue, marked done, until pi's own turn_end for it arrives.
@@ -282,6 +297,7 @@ export function createEngine({
   }
 
   function write(command) {
+    if (command.type === 'prompt') processing();
     if (!state.child || state.exited !== null || state.wedged) throw new DiscordError("engine is not running", 1, { code: "engine-down" });
     state.child.stdin.write(JSON.stringify(command) + "\n");
   }
@@ -301,7 +317,25 @@ export function createEngine({
 
   function stopChild({ graceMs = 5000 } = {}) {
     const child = state.child;
-    if (!child || state.exited !== null) return Promise.resolve(state.exited);
+    if (!child || (state.exited !== null && !managed)) return Promise.resolve(state.exited);
+    if (managed) {
+      let record;
+      try { record = runtime(processingRoot, managed.id); } catch { return Promise.resolve(state.exited); }
+      const signal = createRuntimeSignaller(record, members => updateRuntime(processingRoot, managed.id, { members }));
+      signal('SIGTERM');
+      const began = Date.now();
+      return new Promise(resolve => {
+        let killed = false;
+        const poll = setInterval(() => {
+          let live;
+          try { live = runtimeGroupState(runtime(processingRoot, managed.id)); } catch { live = false; }
+          if (live === false || Date.now() - began > graceMs + 2000) {
+            clearInterval(poll); releaseRuntime(); resolve(state.exited); return;
+          }
+          if (!killed && Date.now() - began >= graceMs) { signal('SIGKILL'); killed = true; }
+        }, 20);
+      });
+    }
     return new Promise((resolve) => {
       const timer = setTimeoutImpl(() => {
         try {
@@ -326,7 +360,23 @@ export function createEngine({
   return {
     start() {
       if (state.child) throw new DiscordError("engine already started", 1);
-      const child = spawn(command, args, { cwd, env, stdio: ["pipe", "pipe", "pipe"] });
+      processing();
+      if (processingRoot) managed = registerRuntime(processingRoot, { kind: 'discord', business: 'instance', run: binding });
+      let child;
+      try {
+        processing();
+        child = spawn(command, args, { cwd, env, stdio: ["pipe", "pipe", "pipe"], ...(processingRoot ? { detached: true } : {}) });
+        if (managed) {
+          const identity = processIdentity(child.pid);
+          if (!identity) throw new DiscordError('engine process identity unavailable', 1);
+          updateRuntime(processingRoot, managed.id, { ...identity, group: true, phase: 'running' });
+          processing();
+        }
+      } catch (e) {
+        if (child?.pid) child.kill('SIGKILL');
+        releaseRuntime();
+        throw e;
+      }
       state.child = child;
       child.stdout.setEncoding("utf8");
       child.stdout.on("data", (chunk) => {
@@ -342,12 +392,14 @@ export function createEngine({
       child.stderr.setEncoding("utf8");
       child.stderr.on("data", (chunk) => log(`pi: ${chunk.trimEnd()}`));
       child.on("error", (err) => {
+        releaseRuntime();
         log(`engine spawn error: ${err.message}`);
         state.exited = { code: null, signal: null, error: err.message };
         failAll("engine-down", `engine failed: ${err.message}`);
         onExit(state.exited);
       });
       child.on("exit", (code, signal) => {
+        releaseRuntime();
         state.exited = { code, signal };
         failAll("engine-down", `engine exited (code ${code}, signal ${signal})`);
         onExit(state.exited);
@@ -358,6 +410,7 @@ export function createEngine({
     // Resolves {text, message, tools, turns, usage, model, provider}. Rejects
     // with DiscordError carrying details.code for the turn record.
     prompt(text, { timeoutMs = 180000 } = {}) {
+      try { processing(); } catch (e) { return Promise.reject(e); }
       if (typeof text !== "string" || text.length === 0) throw new DiscordError("prompt text required", 1);
       const turn = { resolve: null, reject: null, timer: null, grace: null, done: false, accepted: false, tools: new Map(), turns: 0, last: null };
       const done = new Promise((resolve, reject) => {

packages/discord/src/journal.mjs

@@ -21,7 +21,7 @@
 // Directories are 0700, files 0600. Lines are appended, never rewritten.
 
 import {
-  appendFileSync, closeSync, existsSync, mkdirSync, openSync, readdirSync, readFileSync, renameSync, rmSync,
+  appendFileSync, closeSync, constants, existsSync, fstatSync, fsyncSync, mkdirSync, openSync, readdirSync, readFileSync, readSync, renameSync, rmdirSync, rmSync,
   unlinkSync, writeFileSync, writeSync,
 } from "node:fs";
 import { join } from "node:path";
@@ -176,16 +176,64 @@ export function stopRequested(dir) {
 }
 
 export function requestStop(dir, reason = "stop") {
+  return stopLock(dir, () => appendStop(dir, reason));
+}
+
+function stopLock(dir, action) {
+  const lock = join(dir, '.stop.lock');
+  try { mkdirSync(lock, { mode: 0o700 }); }
+  catch { throw new DiscordError('STOP update is locked; refusing', 1); }
+  try { return action(); } finally { rmdirSync(lock); }
+}
+
+function appendStop(dir, reason) {
   const path = stopPath(dir);
-  const fd = openSync(path, "a", 0o600);
+  const fd = openSync(path, constants.O_WRONLY | constants.O_APPEND | constants.O_CREAT | constants.O_NOFOLLOW, 0o600);
   try {
     writeSync(fd, JSON.stringify({ at: new Date().toISOString(), reason }) + "\n");
+    fsyncSync(fd);
   } finally {
     closeSync(fd);
   }
   return path;
 }
 
+const PROCESSING_GENERATION = /^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/;
+function processingStops(dir) {
+  let fd;
+  try {
+    fd = openSync(stopPath(dir), constants.O_RDONLY | constants.O_NOFOLLOW | constants.O_NONBLOCK);
+    const st = fstatSync(fd);
+    if (!st.isFile() || st.uid !== process.getuid() || (st.mode & 0o7777) !== 0o600 || st.size > 65536) return null;
+    const buffer = Buffer.alloc(65537), size = readSync(fd, buffer, 0, buffer.length, 0);
+    if (size > 65536) return null;
+    const bytes = buffer.subarray(0, size);
+    return new TextDecoder('utf8', { fatal: true }).decode(bytes).split('\n').filter(Boolean).map(JSON.parse);
+  } catch (e) { return e.code === 'ENOENT' ? [] : null; }
+  finally { if (fd !== undefined) closeSync(fd); }
+}
+export function requestProcessingStop(dir, generation) {
+  if (!PROCESSING_GENERATION.test(generation)) throw new DiscordError('invalid processing generation', 1);
+  return stopLock(dir, () => {
+    const rows = processingStops(dir);
+    if (rows === null) throw new DiscordError('STOP cannot be verified', 1);
+    const reason = `processing:${generation}`;
+    if (!rows.some(r => r?.reason === reason)) appendStop(dir, reason);
+    return stopPath(dir);
+  });
+}
+export function clearProcessingStop(dir, generation) {
+  if (!PROCESSING_GENERATION.test(generation)) return false;
+  return stopLock(dir, () => {
+    const rows = processingStops(dir);
+    if (!rows?.length || rows.some(r => !r || Object.keys(r).sort().join(',') !== 'at,reason' ||
+        r.reason !== `processing:${generation}` || !Number.isFinite(Date.parse(r.at)) ||
+        new Date(r.at).toISOString() !== r.at)) return false;
+    unlinkSync(stopPath(dir));
+    return true;
+  });
+}
+
 export function clearStop(dir) {
   const path = stopPath(dir);
   if (existsSync(path)) unlinkSync(path);

packages/discord/src/processing.mjs

@@ -0,0 +1,30 @@
+// Host-only adapters for the root coordinator. Workers cannot select these paths.
+import { lstatSync } from 'node:fs';
+import { dirname } from 'node:path';
+import { bindingDataDir } from './binding.mjs';
+import { requestProcessingStop, clearProcessingStop } from './journal.mjs';
+import { listRuntimes, unregisterRuntime } from '../../processing-control/src/runtimes.mjs';
+function journal(root, record) {
+  const dir = bindingDataDir(root, record.run);
+  for (const path of [dirname(dir), dir]) {
+    const st = lstatSync(path);
+    if (!st.isDirectory() || st.isSymbolicLink() || st.uid !== process.getuid() || (st.mode & 0o077))
+      throw new Error('processing-discord-path-unsafe');
+  }
+  return dir;
+}
+export function discordProcessingHooks(dataRoot) {
+  return {
+    beforeStop(record, generation) {
+      if (record.kind === 'discord') requestProcessingStop(journal(dataRoot, record), generation);
+    },
+    onResume(generation) {
+      for (const r of listRuntimes(dataRoot)) {
+        if (r.kind === 'discord' && r.haltGeneration === generation) {
+          clearProcessingStop(journal(dataRoot, r), generation);
+          unregisterRuntime(dataRoot, r.id);
+        }
+      }
+    },
+  };
+}

packages/discord/tests/processing-stop.test.mjs

@@ -0,0 +1,54 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { readFileSync, writeFileSync, symlinkSync, unlinkSync } from 'node:fs';
+import { join } from 'node:path';
+import { randomUUID } from 'node:crypto';
+import { makeRoot } from './helpers.mjs';
+import { ensureJournal, requestStop, stopRequested, stopPath } from '../src/journal.mjs';
+const api = await import('../src/journal.mjs');
+function fixture() { const dir = join(makeRoot(), 'journal'); ensureJournal(dir); return dir; }
+test('resume clears only its own generation-tagged Discord STOP and keeps manual or newer brakes', () => {
+  assert.equal(typeof api.requestProcessingStop, 'function');
+  const dir = fixture(), generation = randomUUID();
+  api.requestProcessingStop(dir, generation); const first = readFileSync(stopPath(dir));
+  api.requestProcessingStop(dir, generation); assert.deepEqual(readFileSync(stopPath(dir)), first);
+  assert.equal(api.clearProcessingStop(dir, randomUUID()), false);
+  assert.equal(api.clearProcessingStop(dir, generation), true); assert.equal(stopRequested(dir), false);
+  api.requestProcessingStop(dir, generation); requestStop(dir, 'cli stop');
+  const mixed = readFileSync(stopPath(dir));
+  assert.equal(api.clearProcessingStop(dir, generation), false); assert.deepEqual(readFileSync(stopPath(dir)), mixed);
+});
+test('unreadable, malformed and symlink STOP never get removed or followed by processing recovery', () => {
+  assert.equal(typeof api.requestProcessingStop, 'function');
+  const dir = fixture(), generation = randomUUID();
+  writeFileSync(stopPath(dir), 'unreadable operator brake\n', { mode: 0o600 });
+  assert.equal(api.clearProcessingStop(dir, generation), false);
+  unlinkSync(stopPath(dir)); const outside = join(dir, 'outside');
+  writeFileSync(outside, 'untouched', { mode: 0o600 }); symlinkSync(outside, stopPath(dir));
+  assert.equal(api.clearProcessingStop(dir, generation), false);
+  assert.throws(() => api.requestProcessingStop(dir, generation));
+  assert.equal(readFileSync(outside, 'utf8'), 'untouched');
+});
+
+test('coordinator halt writes the Discord brake and resume clears only its own stopped runtime', async () => {
+  const { initializeControl } = await import('../../processing-control/src/state.mjs');
+  const { registerRuntime, updateRuntime } = await import('../../processing-control/src/runtimes.mjs');
+  const { createProcessing } = await import('../../processing-control/src/coordinator.mjs');
+  const { discordProcessingHooks } = await import('../src/processing.mjs');
+  const root = makeRoot(); initializeControl(root);
+  const dir = join(root, 'discord', 'test-seat'); ensureJournal(dir);
+  const processing = createProcessing({ dataRoot: root, ...discordProcessingHooks(root) });
+  const first = registerRuntime(root, { kind: 'discord', business: 'instance', run: 'test-seat' });
+  updateRuntime(root, first.id, { phase: 'ended' });
+  const halted = await processing.halt({ business: 'demo', human: 'jason' });
+  assert.equal(halted.quiescent, true); assert.equal(stopRequested(dir), true);
+  await processing.resume({ business: 'demo', human: 'jason', generation: halted.generation });
+  assert.equal(stopRequested(dir), false);
+  const second = registerRuntime(root, { kind: 'discord', business: 'instance', run: 'test-seat' });
+  updateRuntime(root, second.id, { phase: 'ended' });
+  const again = await processing.halt({ business: 'demo', human: 'jason' });
+  requestStop(dir, 'cli stop'); const bytes = readFileSync(stopPath(dir));
+  await processing.resume({ business: 'demo', human: 'jason', generation: again.generation });
+  assert.deepEqual(readFileSync(stopPath(dir)), bytes);
+  await processing.close();
+});

packages/discord/tests/processing.test.mjs

@@ -0,0 +1,76 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { spawnSync } from 'node:child_process';
+import { mkdirSync, unlinkSync, readFileSync } from 'node:fs';
+import { join } from 'node:path';
+import { createConnector } from '../src/connector.mjs';
+import { initializeControl, assertProcessing, transition } from '../../processing-control/src/state.mjs';
+import { makeRoot, makeRepo, makeDeployment, binding, message, fakeRest, fakeGateway, fakeEngine } from './helpers.mjs';
+import { appendOutbox, ensureJournal, readOutbox, listTurns } from '../src/journal.mjs';
+const actor = { business: 'demo', human: 'jason', halted: true };
+function fixture() {
+  const root = makeRoot(); initializeControl(root);
+  const journalDir = join(root, 'journal'), rest = fakeRest(), gateway = fakeGateway(), engine = fakeEngine({ replies: [{ text: 'reply' }] });
+  const processing = () => assertProcessing(root);
+  const options = { binding: binding(), journalDir, rest, gateway, engine, processing };
+  return { root, journalDir, rest, gateway, engine, options };
+}
+test('halted connector refuses before outbox reconciliation, engine or gateway start', async () => {
+  const f = fixture(); ensureJournal(f.journalDir);
+  appendOutbox(f.journalDir, { nonce: 'pending', channelId: '100000000000000200', status: 'intent', content: 'do not replay', at: new Date().toISOString() });
+  transition(f.root, actor);
+  await assert.rejects(createConnector(f.options).start(), e => e.code === 'processing-halted');
+  assert.equal(f.rest.calls.length, 0); assert.equal(f.engine.started, false);
+});
+test('halt arriving during startup reconciliation prevents engine and gateway start', async () => {
+  const f = fixture(); ensureJournal(f.journalDir);
+  appendOutbox(f.journalDir, { nonce: 'pending', channelId: '100000000000000200', status: 'intent', content: 'first', at: new Date().toISOString() });
+  const create = f.rest.createMessage;
+  f.rest.createMessage = async (...args) => { const result = await create(...args); transition(f.root, actor); return result; };
+  await assert.rejects(createConnector(f.options).start(), e => e.code === 'processing-halted');
+  assert.equal(f.engine.started, false);
+});
+test('halted connector refuses a new inbound turn before claiming inbox or invoking the engine', async () => {
+  const f = fixture(), connector = createConnector(f.options); await connector.start();
+  transition(f.root, actor);
+  const answer = await connector.handleMessage(message());
+  assert.equal(answer.accepted, false); assert.equal(answer.reason, 'processing-halted');
+  assert.equal(connector.inboxSize, 0); assert.equal(f.engine.prompts.length, 0);
+  await connector.stop();
+});
+test('halt during a model turn never sends its answer or a fallback failure message', async () => {
+  const f = fixture();
+  f.engine.prompt = async () => { transition(f.root, actor); return { text: 'must not send', usage: { input: 1, output: 1 } }; };
+  const connector = createConnector(f.options); await connector.start();
+  const turn = await connector.handleMessage(message()); await turn.turn;
+  assert.equal(f.rest.calls.length, 0);
+  assert.equal(listTurns(f.journalDir)[0].error.code, 'processing-halted');
+  await connector.stop();
+});
+test('Discord run and recover refuse a halted root before reading a token or reaching network', () => {
+  const root = makeRoot(), repo = makeRepo(root), d = makeDeployment(root);
+  mkdirSync(d.dataRoot, { recursive: true, mode: 0o700 }); initializeControl(d.dataRoot);
+  transition(d.dataRoot, actor); unlinkSync(d.tokenFile);
+  for (const command of ['run', 'recover']) {
+    const r = spawnSync(process.execPath, [new URL('../src/cli.mjs', import.meta.url).pathname, command, d.raw.name, '--config', d.config, '--repo', repo], { encoding: 'utf8', timeout: 5000 });
+    assert.equal(r.status, 3, r.stderr); assert.match(r.stderr, /processing-halted/);
+  }
+});
+
+test('Discord engine publishes a verified group and a root halt kills it independently of the connector', async t => {
+  const { createEngine } = await import('../src/engine-pi.mjs');
+  const { listRuntimes, sweepRuntimes, processIdentity } = await import('../../processing-control/src/runtimes.mjs');
+  const f = fixture();
+  const engine = createEngine({ command: process.execPath,
+    args: [new URL('./fake-pi.mjs', import.meta.url).pathname], cwd: f.root,
+    env: { ...process.env }, processingRoot: f.root, binding: 'test-seat' });
+  t.after(() => engine.stop({ graceMs: 50 }));
+  const child = engine.start();
+  const tracked = listRuntimes(f.root);
+  assert.equal(tracked.length, 1); assert.equal(tracked[0].pid, child.pid);
+  assert.equal(tracked[0].kind, 'discord'); assert.equal(tracked[0].group, true);
+  const halted = transition(f.root, actor);
+  await assert.rejects(engine.prompt('not admitted'), e => e.code === 'processing-halted');
+  const result = await sweepRuntimes(f.root, halted.generation, { graceMs: 80, killWaitMs: 1000 });
+  assert.equal(result.quiescent, true); assert.equal(processIdentity(child.pid), null);
+});

packages/processing-control/README.md

@@ -0,0 +1,42 @@
+# Instance processing control
+
+The durable switch is `<dataRoot>/control/processing.json`, using the root resolved
+by the existing system configuration loader. All businesses in that root share
+one switch; separate roots remain independent. No package selects an instance by
+business name or systemd unit name.
+
+A human runs `mosaic halt [--business ID]`, `mosaic processing status --json` and
+`mosaic resume [--business ID]`. The business chooses the human proof context.
+Halt publishes state before waiting for stops. Resume checks the displayed
+generation and refuses while a stop is unresolved. Neither agents nor tester
+sessions can change the switch. CLI channel settings cannot disable recovery.
+
+The bus remains available for reads and human management. Managed processing,
+new sessions, task containers, tracker activity and outbound notification stop.
+Native diagnostic/development seats remain available. A remote request already
+accepted cannot be undone: its completion or unknown outcome remains evidence.
+No task is automatically retried on resume.
+
+The trusted host explicitly initializes the first off document. Once control/
+exists, a missing, malformed, unsafe or oversized state refuses work. Recovery
+is halt, then resume; unsafe parent ownership/path boundaries require operator
+repair. Never delete the file to clear a halt. State publication uses exclusive
+temporary files, fsync and atomic rename. Run evidence remains write-once.
+
+Runtime receipts bind generated ids to the canonical root, boot id and process
+start ticks or inspected container id and labels. Stops begin concurrently,
+TERM first, then KILL after five seconds, with two seconds for observation.
+Unknown remains unknown and prevents resume. Stop receipts are write-once and
+mirrored into reserved bus actions. An interrupted Docker CLI is not evidence
+that its container stopped; a container that cannot be inspected stays unknown.
+
+Task containers mount the whole control directory read-only, below the existing
+root mount. The image entrypoint uses the shared strict reader and admission
+generation. A row-191 upgrade must stop old processing before the first trusted
+initialization and align the image, bus and copy in a separately approved window.
+Nothing in a code build performs that activation.
+
+The Console status and persistent halted banner work read-only. The controls
+require the existing authenticated human write path and `--send`; during Q175's
+interim the UI explains that the instance CLI is the working path. No write
+exception or alternate authentication scheme is introduced.

packages/processing-control/package.json

@@ -0,0 +1,6 @@
+{
+  "name": "@mosaic/processing-control",
+  "private": true,
+  "type": "module",
+  "scripts": { "test": "node --test tests/*.test.mjs" }
+}

packages/processing-control/src/container-cli.mjs

@@ -0,0 +1,23 @@
+#!/usr/bin/env node
+// The shell launchers already load/release/bootstrap. Resolve the selected config again here.
+import { randomUUID } from 'node:crypto';
+import { loadSystem } from '../../cli/src/config.mjs';
+import { runContainer } from './containers.mjs';
+import { unregisterRuntime } from './runtimes.mjs';
+import { initializeControl, assertProcessing } from './state.mjs';
+try {
+  const system = loadSystem();
+  initializeControl(system.dataRoot);
+  assertProcessing(system.dataRoot);
+  const args = process.argv.slice(2), tty = args[0] === '--tty';
+  if (args.length === 1 && args[0] === '--check') process.exit(0);
+  if (tty) args.shift();
+  const result = runContainer(system.dataRoot, { kind: 'container', business: 'instance', run: randomUUID() },
+    { tty, args, env: process.env, stdio: 'inherit' });
+  if (!result.haltGeneration && !result.proc.error && result.proc.status === 0) unregisterRuntime(system.dataRoot, result.managed.id);
+  if (result.proc.error) throw result.proc.error;
+  process.exit(result.proc.status ?? 1);
+} catch (e) {
+  process.stderr.write(`processing: ${e.code?.startsWith('processing-') ? e.code : 'container-launch-failed'}\n`);
+  process.exit(3);
+}

packages/processing-control/src/containers.mjs

@@ -0,0 +1,86 @@
+import { randomUUID } from 'node:crypto';
+import { spawnSync, execFile } from 'node:child_process';
+import { promisify } from 'node:util';
+import { initializeControl, assertProcessing } from './state.mjs';
+import { registerRuntime, updateRuntime, runtime, rootTag } from './runtimes.mjs';
+const execute = promisify(execFile);
+const pause = ms => new Promise(resolve => setTimeout(resolve, ms));
+export function prepareContainer(dataRoot, record) {
+  initializeControl(dataRoot);
+  const state = assertProcessing(dataRoot);
+  const containerName = `mosaic-${rootTag(dataRoot).slice(0, 12)}-${randomUUID()}`;
+  const managed = registerRuntime(dataRoot, { ...record, containerName });
+  assertProcessing(dataRoot, state.generation);
+  return managed;
+}
+export function containerArgs(record, { tty = false, args = [] } = {}) {
+  return ['compose', 'run', '--rm', ...(!tty ? ['-T'] : []), '--name', record.containerName,
+    '--label', `mosaic.root=${record.root}`, '--label', `mosaic.runtime=${record.id}`,
+    '-e', `MOSAIC_PROCESSING_GENERATION=${record.generation}`, 'mosaic-agent', ...args];
+}
+export function runContainer(dataRoot, record, { tty = false, args = [], ...options } = {}) {
+  const managed = prepareContainer(dataRoot, record);
+  assertProcessing(dataRoot, managed.generation);
+  // Keep this synchronous. The independent broker sweeps the prepublished name while this waits.
+  const proc = spawnSync('docker', containerArgs(managed, { tty, args }), options);
+  const current = runtime(dataRoot, managed.id);
+  // An interrupted Docker client is not proof its container exited. Keep that receipt for inspection.
+  if (!proc.error && proc.status === 0) updateRuntime(dataRoot, managed.id, { phase: 'ended' });
+  return { proc, managed, haltGeneration: current.haltGeneration ?? null };
+}
+export function createContainerStopper({ dataRoot = null, docker = async args => {
+  const r = await execute('docker', args, { encoding: 'utf8', timeout: 2000, maxBuffer: 131072 });
+  return r.stdout;
+} } = {}) {
+  return async (record, { graceMs = 5000, killWaitMs = 2000 } = {}) => {
+    const signals = [];
+    let id = record.containerId ?? null, seen = false;
+    const start = Date.now(), termEnd = start + graceMs, end = termEnd + killWaitMs;
+    async function inspect(target) {
+      const doc = JSON.parse(await docker(['inspect', '--format', '{{json .}}', target]));
+      if (!doc || !/^[a-f0-9]{64}$/.test(doc.Id) || doc.Name !== '/' + record.containerName ||
+          doc.Config?.Labels?.['mosaic.root'] !== record.root || doc.Config?.Labels?.['mosaic.runtime'] !== record.id ||
+          typeof doc.State?.Running !== 'boolean' || (id && doc.Id !== id)) {
+        const error = new Error('container identity mismatch'); error.code = 'identity-mismatch'; throw error;
+      }
+      if (!id) {
+        id = doc.Id;
+        if (dataRoot) updateRuntime(dataRoot, record.id, { containerId: id });
+      }
+      seen = true;
+      return doc;
+    }
+    while (Date.now() <= end) {
+      try {
+        const doc = await inspect(id ?? record.containerName);
+        if (!doc.State.Running) return { outcome: signals.includes('SIGKILL') ? 'killed' : signals.length ? 'terminated' : 'already-exited', signals };
+        const next = !signals.length ? 'TERM' : Date.now() >= termEnd && !signals.includes('SIGKILL') ? 'KILL' : null;
+        if (next) {
+          // Revalidate immediately before each signal, targeting the immutable inspected id.
+          const checked = await inspect(id);
+          if (!checked.State.Running) continue;
+          await docker(['kill', '--signal', next, id]);
+          signals.push('SIG' + next);
+        }
+      } catch (e) {
+        // A missing name can still be a queued create. Only a container observed before a signal
+        // and then removed by --rm is known to have finished. Never signal on an inspect failure.
+        if (e.code === 'identity-mismatch') return { outcome: 'unknown', signals };
+        if (id && seen && signals.length) {
+          try {
+            const listed = await docker(['ps', '--all', '--no-trunc', '--filter', `id=${id}`, '--format', '{{.ID}}']);
+            if (listed.trim() === '') return { outcome: signals.includes('SIGKILL') ? 'killed' : 'terminated', signals };
+          } catch { /* a failed Docker request proves nothing about the workload */ }
+        }
+        if (dataRoot) {
+          try {
+            if (runtime(dataRoot, record.id).phase === 'ended')
+              return { outcome: signals.includes('SIGKILL') ? 'killed' : signals.length ? 'terminated' : 'already-exited', signals };
+          } catch { return { outcome: 'unknown', signals }; }
+        }
+      }
+      await pause(Math.min(20, Math.max(1, end - Date.now())));
+    }
+    return { outcome: 'unknown', signals };
+  };
+}

packages/processing-control/src/coordinator.mjs

@@ -0,0 +1,74 @@
+import { initializeControl, processingStatus, transition, ProcessingError } from './state.mjs';
+import { readStops, sweepRuntimes } from './runtimes.mjs';
+import { withProcessing, currentProcessing } from './effects.mjs';
+
+// The control bus stays reachable. Only its processing, supervised workloads and background effects stop.
+export function createProcessing({ dataRoot, graceMs = 5000, killWaitMs = 2000, containerStop = null,
+  onTransition = () => {}, onStop = () => {}, beforeStop = () => {}, onResume = () => {}, log = () => {} }) {
+  try { initializeControl(dataRoot); } catch (e) {
+    if (!e.code?.startsWith('processing-')) throw e;
+  }
+  let active = null, timer = null, closed = false;
+  let last = { quiescent: true, remaining: 0, stopped: 0 };
+  let settledGeneration = null;
+  const read = () => {
+    const state = processingStatus(dataRoot);
+    const counts = state.invalid || (state.halted && state.generation !== settledGeneration)
+      ? { quiescent: false, remaining: null, stopped: 0 } : last;
+    return { ...state, ...counts, stopping: active !== null };
+  };
+  function reconcile() {
+    if (active) return active;
+    const state = processingStatus(dataRoot);
+    if (state.invalid) return Promise.resolve({ quiescent: false, remaining: null, stopped: 0 });
+    active = Promise.resolve().then(async () => {
+      await onTransition(state);
+      if (state.halted) {
+        const result = await sweepRuntimes(dataRoot, state.generation, { graceMs, killWaitMs, containerStop, beforeStop });
+        for (const stop of readStops(dataRoot, state.generation)) await onStop(stop);
+        const { results, ...summary } = result;
+        last = summary;
+        settledGeneration = state.generation;
+      } else last = { quiescent: true, remaining: 0, stopped: 0 };
+      return last;
+    }).finally(() => { active = null; });
+    return active;
+  }
+  return {
+    read,
+    work: fn => withProcessing(dataRoot, fn),
+    guard: () => currentProcessing()?.guard(),
+    signal: () => currentProcessing()?.signal,
+    stopReceipts: generation => readStops(dataRoot, generation),
+    // Publication is synchronous: no timer/model/HTTP wait can delay the admission fence.
+    halt(actor) {
+      const published = transition(dataRoot, { ...actor, halted: true });
+      return reconcile().then(summary => ({ ...published, ...summary }));
+    },
+    async resume(actor) {
+      if (active) throw new ProcessingError('processing-stop-pending');
+      const state = processingStatus(dataRoot);
+      if (state.invalid) throw new ProcessingError(state.code);
+      if (state.generation !== actor.generation) throw new ProcessingError('processing-generation-changed');
+      const summary = await reconcile();
+      if (!summary.quiescent) throw new ProcessingError('processing-stop-pending');
+      await onResume(state.generation);
+      const published = transition(dataRoot, { ...actor, halted: false });
+      await onTransition(published);
+      last = { quiescent: true, remaining: 0, stopped: 0 };
+      return { ...published, ...last };
+    },
+    reconcile,
+    start() {
+      if (timer || closed) return;
+      const tick = () => {
+        if (!active && processingStatus(dataRoot).halted) reconcile().catch(() => log('processing-reconcile-failed'));
+      };
+      tick(); timer = setInterval(tick, 250); timer.unref();
+    },
+    async close() {
+      closed = true; clearInterval(timer); timer = null;
+      await active;
+    },
+  };
+}

packages/processing-control/src/effects.mjs

@@ -0,0 +1,61 @@
+import { AsyncLocalStorage } from 'node:async_hooks';
+import { randomUUID } from 'node:crypto';
+import { assertProcessing } from './state.mjs';
+import { registerRuntime, updateRuntime, unregisterRuntime, processIdentity, createRuntimeSignaller, runtimeGroupState, runtime } from './runtimes.mjs';
+const contexts = new AsyncLocalStorage();
+export const currentProcessing = () => contexts.getStore();
+// Trusted compensation/temporary-file cleanup only; never an agent work entry point.
+export const withoutProcessing = fn => contexts.run(undefined, fn);
+export async function withProcessing(dataRoot, fn) {
+  const parent = currentProcessing();
+  const generation = assertProcessing(dataRoot, parent?.dataRoot === dataRoot ? parent.generation : null).generation;
+  const pending = registerRuntime(dataRoot, { kind: 'effect', business: 'instance', run: randomUUID() });
+  const controller = new AbortController();
+  const children = [];
+  const guard = () => assertProcessing(dataRoot, generation);
+  const poll = setInterval(() => {
+    try { guard(); } catch (e) { controller.abort(e); }
+  }, 25);
+  poll.unref();
+  const scope = {
+    dataRoot, generation, signal: controller.signal, guard,
+    track(child) {
+      const identity = processIdentity(child.pid);
+      if (!identity) return;
+      children.push(new Promise(resolve => child.once('close', resolve)));
+      let record;
+      try { record = registerRuntime(dataRoot, { kind: 'effect', business: 'instance', run: randomUUID() }); }
+      catch (e) {
+        createRuntimeSignaller({ ...identity, kind: 'effect', group: true })('SIGKILL');
+        throw e;
+      }
+      const running = updateRuntime(dataRoot, record.id, { ...identity, group: true, phase: 'running' });
+      const signal = createRuntimeSignaller(running, members => updateRuntime(dataRoot, record.id, { members }));
+      let kill = null;
+      const cancel = () => {
+        signal('SIGTERM');
+        kill = setTimeout(() => signal('SIGKILL'), 5000);
+        kill.unref();
+      };
+      controller.signal.addEventListener('abort', cancel, { once: true });
+      child.once('close', () => {
+        controller.signal.removeEventListener('abort', cancel); clearTimeout(kill);
+        try {
+          if (runtimeGroupState(runtime(dataRoot, record.id)) === false) unregisterRuntime(dataRoot, record.id);
+        } catch { /* keep unverifiable receipts for reconciliation */ }
+      });
+      try { guard(); } catch (e) { controller.abort(e); }
+      if (controller.signal.aborted && kill === null) cancel();
+    },
+  };
+  try {
+    guard();
+    const result = await contexts.run(scope, () => fn(scope));
+    guard();
+    return result;
+  } finally {
+    clearInterval(poll);
+    await Promise.all(children);
+    unregisterRuntime(dataRoot, pending.id);
+  }
+}

packages/processing-control/src/entrypoint.mjs

@@ -0,0 +1,7 @@
+// Image-baked final admission, using the same strict state reader as the host.
+import { assertProcessing } from './state.mjs';
+try { assertProcessing(process.argv[2], process.env.MOSAIC_PROCESSING_GENERATION ?? null); }
+catch (e) {
+  process.stderr.write(`run-agent: ${e.code?.startsWith('processing-') ? e.code : 'processing-state-invalid'}\n`);
+  process.exit(3);
+}

packages/processing-control/src/runtimes.mjs

@@ -0,0 +1,405 @@
+// Only host-side starters publish these identities. A receipt is never a request from a worker.
+import { randomUUID, createHash } from 'node:crypto';
+import { constants, closeSync, fstatSync, fsyncSync, lstatSync, mkdirSync, openSync, readFileSync, linkSync,
+  readdirSync, readSync, renameSync, unlinkSync, writeFileSync } from 'node:fs';
+import { dirname, join } from 'node:path';
+import { controlDirectory, readControl, assertProcessing, ProcessingError } from './state.mjs';
+
+const UUID = /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/;
+const ID = /^[a-zA-Z0-9][a-zA-Z0-9_.:@/-]{0,159}$/;
+const fail = () => { throw new ProcessingError('processing-runtime-invalid'); };
+const wait = ms => new Promise(resolve => setTimeout(resolve, ms));
+export const rootTag = root => createHash('sha256').update(dirname(controlDirectory(root))).digest('hex');
+export function processIdentity(pid) {
+  try {
+    const raw = readFileSync(`/proc/${pid}/stat`, 'utf8');
+    const fields = raw.slice(raw.lastIndexOf(')') + 2).split(' ');
+    if (fields[0] === 'Z') return null;
+    return { pid, startTime: fields[19], boot: readFileSync('/proc/sys/kernel/random/boot_id', 'utf8').trim() };
+  } catch { return null; }
+}
+function alive(identity) {
+  if (!identity || !Number.isSafeInteger(identity.pid) || identity.pid < 2 ||
+      typeof identity.startTime !== 'string' || !UUID.test(identity.boot)) return null;
+  const current = processIdentity(identity.pid);
+  if (current) return current.boot === identity.boot && current.startTime === identity.startTime;
+  try {
+    const stat = readFileSync(`/proc/${identity.pid}/stat`, 'utf8');
+    if (stat.slice(stat.lastIndexOf(')') + 2).split(' ')[0] === 'Z') return false;
+    process.kill(identity.pid, 0); return null;
+  }
+  catch (e) {
+    if (e.code === 'ESRCH') return false;
+    if (e.code === 'ENOENT') {
+      try { process.kill(identity.pid, 0); } catch (gone) { if (gone.code === 'ESRCH') return false; }
+    }
+    return null;
+  }
+}
+function directory(root, ...segments) {
+  // Checking the state also validates the service-owned control parent. A halted state is fine here.
+  readControl(root);
+  let dir = controlDirectory(root);
+  for (const name of segments) {
+    if (!['runtimes', 'stops', 'run-stops'].includes(name) && !UUID.test(name)) fail();
+    const parent = dir;
+    dir = join(dir, name);
+    let made = false;
+    try { mkdirSync(dir, { mode: 0o700 }); made = true; }
+    catch (e) { if (e.code !== 'EEXIST') fail(); }
+    const st = lstatSync(dir);
+    if (!st.isDirectory() || st.isSymbolicLink() || st.uid !== process.getuid() || (st.mode & 0o7777) !== 0o700) fail();
+    if (made) {
+      const fd = openSync(parent, constants.O_RDONLY | constants.O_DIRECTORY | constants.O_NOFOLLOW);
+      try { fsyncSync(fd); } finally { closeSync(fd); }
+    }
+  }
+  return dir;
+}
+function read(file) {
+  let fd;
+  try {
+    fd = openSync(file, constants.O_RDONLY | constants.O_NOFOLLOW | constants.O_NONBLOCK);
+    const st = fstatSync(fd);
+    if (!st.isFile() || st.uid !== process.getuid() || (st.mode & 0o7777) !== 0o600 || st.size > 16384) fail();
+    const buffer = Buffer.alloc(16385), n = readSync(fd, buffer, 0, buffer.length, 0);
+    if (n > 16384) fail();
+    return JSON.parse(new TextDecoder('utf8', { fatal: true }).decode(buffer.subarray(0, n)));
+  } catch { fail(); }
+  finally { if (fd !== undefined) closeSync(fd); }
+}
+function write(file, doc, once = false) {
+  let fd, dirfd;
+  const temp = join(dirname(file), `.receipt-${randomUUID()}`);
+  try {
+    fd = openSync(temp, constants.O_WRONLY | constants.O_CREAT | constants.O_EXCL | constants.O_NOFOLLOW, 0o600);
+    writeFileSync(fd, JSON.stringify(doc) + '\n'); fsyncSync(fd); closeSync(fd); fd = undefined;
+    if (once) linkSync(temp, file);
+    else renameSync(temp, file);
+    dirfd = openSync(dirname(file), constants.O_RDONLY | constants.O_DIRECTORY | constants.O_NOFOLLOW);
+    fsyncSync(dirfd);
+    return doc;
+  } catch (e) {
+    if (once && e.code === 'EEXIST') return read(file);
+    fail();
+  } finally {
+    if (fd !== undefined) closeSync(fd);
+    if (dirfd !== undefined) closeSync(dirfd);
+    try { unlinkSync(temp); } catch (e) { if (e.code !== 'ENOENT') fail(); }
+  }
+}
+const fields = ['version', 'id', 'root', 'kind', 'business', 'run', 'generation', 'phase', 'supervisor',
+  'pid', 'startTime', 'boot', 'group', 'runnerPid', 'runnerStartTime', 'containerName', 'containerId', 'haltGeneration', 'members'];
+function validate(r) {
+  if (!r || typeof r !== 'object' || Array.isArray(r) || Object.keys(r).some(k => !fields.includes(k)) ||
+      r.version !== 1 || !UUID.test(r.id) || !/^[0-9a-f]{64}$/.test(r.root) ||
+      !['session', 'task', 'container', 'discord', 'effect'].includes(r.kind) ||
+      !UUID.test(r.generation) || !['starting', 'running', 'ended'].includes(r.phase) ||
+      typeof r.business !== 'string' || !ID.test(r.business) || typeof r.run !== 'string' || !ID.test(r.run) ||
+      !r.supervisor || !Number.isSafeInteger(r.supervisor.pid) || !UUID.test(r.supervisor.boot)) fail();
+  if (r.pid !== undefined && (!Number.isSafeInteger(r.pid) || r.pid < 2 ||
+      typeof r.startTime !== 'string' || !/^\d+$/.test(r.startTime) || !UUID.test(r.boot))) fail();
+  if (r.group !== undefined && typeof r.group !== 'boolean') fail();
+  if (r.runnerPid !== undefined && (!Number.isSafeInteger(r.runnerPid) || r.runnerPid < 2 ||
+      typeof r.runnerStartTime !== 'string' || !/^\d+$/.test(r.runnerStartTime))) fail();
+  if (r.haltGeneration !== undefined && !UUID.test(r.haltGeneration)) fail();
+  if (r.members !== undefined && (!r.group || !Array.isArray(r.members) || r.members.length > 64 ||
+      r.members.some(m => !m || Object.keys(m).sort().join(',') !== 'boot,pid,startTime' ||
+        !Number.isSafeInteger(m.pid) || m.pid < 2 || typeof m.startTime !== 'string' ||
+        !/^\d+$/.test(m.startTime) || m.boot !== r.boot))) fail();
+  if (r.containerName !== undefined && !/^mosaic-[a-f0-9]{12}-[a-f0-9-]{36}$/.test(r.containerName)) fail();
+  if (r.containerId !== undefined && !/^[a-f0-9]{64}$/.test(r.containerId)) fail();
+  return r;
+}
+export function registerRuntime(root, record) {
+  const admission = assertProcessing(root);
+  const r = validate({ ...record, version: 1, id: randomUUID(), root: rootTag(root),
+    generation: admission.generation, phase: 'starting', supervisor: processIdentity(process.pid) });
+  const file = join(directory(root, 'runtimes'), r.id + '.json');
+  write(file, r, true);
+  try { assertProcessing(root, admission.generation); }
+  catch (e) { unlinkSync(file); throw e; }
+  return r;
+}
+export function runtime(root, id) {
+  if (!UUID.test(id)) fail();
+  const r = validate(read(join(directory(root, 'runtimes'), id + '.json')));
+  if (r.id !== id || r.root !== rootTag(root)) fail();
+  return r;
+}
+export function updateRuntime(root, id, update) {
+  if (Object.keys(update).some(k => !['pid', 'startTime', 'boot', 'group', 'runnerPid', 'runnerStartTime',
+    'containerId', 'phase', 'haltGeneration', 'members'].includes(k))) fail();
+  const r = validate({ ...runtime(root, id), ...update });
+  return write(join(directory(root, 'runtimes'), id + '.json'), r);
+}
+export function unregisterRuntime(root, id) {
+  runtime(root, id);
+  unlinkSync(join(directory(root, 'runtimes'), id + '.json'));
+}
+export function listRuntimes(root) {
+  return readdirSync(directory(root, 'runtimes')).filter(n => !n.startsWith('.receipt-')).map(name => {
+    if (!name.endsWith('.json') || !UUID.test(name.slice(0, -5))) fail();
+    return runtime(root, name.slice(0, -5));
+  });
+}
+export function readStops(root, generation) {
+  if (!UUID.test(generation)) fail();
+  return readdirSync(directory(root, 'stops', generation)).filter(name => !name.startsWith('.receipt-')).map(name => read(join(directory(root, 'stops', generation), name)))
+    .sort((a, b) => a.at.localeCompare(b.at) || a.id.localeCompare(b.id));
+}
+function stopRecord(root, generation, r, outcome, signals, problem = null, receipt = null) {
+  const doc = { version: 1, id: randomUUID(), generation, runtime: r.id, kind: r.kind,
+    business: r.business, run: r.run, ...(receipt ? { stop: receipt.id, reason: receipt.reason, owner: receipt.owner } : {}), at: new Date().toISOString(), outcome, signals, ...(problem ? { problem } : {}),
+    identity: r.pid ? { pid: r.pid, startTime: r.startTime, boot: r.boot } : null };
+  return write(join(directory(root, 'stops', generation), `${r.id}.${outcome}.json`), doc, true);
+}
+function groupOf(pid) {
+  try {
+    const stat = readFileSync(`/proc/${pid}/stat`, 'utf8');
+    return Number(stat.slice(stat.lastIndexOf(')') + 2).split(' ')[2]);
+  } catch { return null; }
+}
+function groupMembers(pgid) {
+  return readdirSync('/proc').filter(n => /^\d+$/.test(n)).map(Number)
+    .filter(pid => groupOf(pid) === pgid).map(processIdentity).filter(Boolean);
+}
+function signal(r, sig, members) {
+  if (sig === 'SIGTERM' && r.kind === 'session' && r.runnerPid !== undefined) {
+    const runner = { pid: r.runnerPid, startTime: r.runnerStartTime, boot: r.boot };
+    if (alive(r) !== true || alive(runner) !== true || groupOf(runner.pid) !== r.pid) return false;
+    try { process.kill(runner.pid, sig); return true; } catch { return false; }
+  }
+  // A surviving, start-time-checked member anchors the original group even after its leader exits.
+  // Never signal a recycled group merely because its numeric id matches.
+  const verified = r.group
+    ? members.some(m => alive(m) === true && groupOf(m.pid) === r.pid)
+    : alive(r) === true;
+  if (!verified) return false;
+  try { process.kill(r.group ? -r.pid : r.pid, sig); return true; } catch { return false; }
+}
+export function createRuntimeSignaller(record, onMembers = () => {}) {
+  let members = record.group && alive(record) === true && groupOf(record.pid) === record.pid
+    ? groupMembers(record.pid) : record.members ?? [];
+  return sig => {
+    if (record.group && members.some(m => alive(m) === true && groupOf(m.pid) === record.pid)) {
+      const found = groupMembers(record.pid);
+      members = [...members, ...found.filter(m => !members.some(old => old.pid === m.pid && old.startTime === m.startTime))];
+    }
+    try { if (record.group) onMembers(members.slice(0, 64)); } catch { return false; }
+    return signal(record, sig, members);
+  };
+}
+export function runtimeGroupState(record) {
+  if (!record.group) return alive(record);
+  if (alive(record) === true && groupOf(record.pid) === record.pid) return true;
+  if ((record.members ?? []).some(m => alive(m) === true && groupOf(m.pid) === record.pid)) return true;
+  // An unknown survivor may be ours or a recycled group. Neither permits a signal or quiescence.
+  return groupMembers(record.pid).length ? null : false;
+}
+// One first-owner stop operation per canonical root/business/run. Never async-wrap the
+// exported function: callers joining an in-flight stop must receive the identical Promise.
+const stopping = new Map();
+const STOP_GRACE_MS = 5000, STOP_OBSERVE_MS = 2000;
+function stopKey(root, business, run) {
+  const hex = createHash('sha256').update(JSON.stringify([rootTag(root), business, run])).digest('hex');
+  return `${hex.slice(0,8)}-${hex.slice(8,12)}-${hex.slice(12,16)}-${hex.slice(16,20)}-${hex.slice(20,32)}`;
+}
+function stopPaths(root, key) {
+  const dir = directory(root, 'run-stops');
+  return { claim: join(dir, key + '.claim.json'), result: join(dir, key + '.result.json') };
+}
+function optionalRead(file) {
+  try { lstatSync(file); } catch (e) { if (e.code === 'ENOENT') return null; throw e; }
+  return read(file);
+}
+function stopResult(doc, expected) {
+  const fields = ['version','id','root','business','run','reason','owner','at','runtime','kind','outcome','signals','identity'];
+  if (!doc || typeof doc !== 'object' || Array.isArray(doc) ||
+      Object.keys(doc).length !== fields.length || Object.keys(doc).some(k => !fields.includes(k)) ||
+      doc.version !== 1 || doc.business !== expected.business || doc.run !== expected.run ||
+      doc.root !== expected.root || !UUID.test(doc.id) || !['fire','kill-switch'].includes(doc.reason) ||
+      typeof doc.at !== 'string' || !Number.isFinite(Date.parse(doc.at)) || new Date(doc.at).toISOString() !== doc.at ||
+      (doc.runtime !== null && !UUID.test(doc.runtime)) ||
+      (doc.kind !== null && !['session','task','container','discord','effect'].includes(doc.kind)) ||
+      !['stopped','killed','alive','identity-changed','unknown'].includes(doc.outcome) ||
+      !Array.isArray(doc.signals) || doc.signals.length > 2 ||
+      doc.signals.some(s => !['SIGTERM','SIGKILL'].includes(s)) || new Set(doc.signals).size !== doc.signals.length ||
+      (doc.signals.length === 2 && doc.signals.join(',') !== 'SIGTERM,SIGKILL') ||
+      !doc.owner || typeof doc.owner !== 'object' || Array.isArray(doc.owner)) fail();
+  if (doc.reason === 'fire' ? Object.keys(doc.owner).join(',') !== 'decision' || typeof doc.owner.decision !== 'string' || !ID.test(doc.owner.decision) :
+      Object.keys(doc.owner).join(',') !== 'generation' || !UUID.test(doc.owner.generation)) fail();
+  if (doc.identity !== null && (!doc.identity || Object.keys(doc.identity).sort().join(',') !== 'boot,pid,startTime' ||
+      !Number.isSafeInteger(doc.identity.pid) || doc.identity.pid < 2 ||
+      typeof doc.identity.startTime !== 'string' || !/^\d+$/.test(doc.identity.startTime) || !UUID.test(doc.identity.boot))) fail();
+  return { run: doc.run, outcome: doc.outcome, pid: doc.identity?.pid ?? null,
+    signals: doc.signals, receipt: doc };
+}
+export function stopRun(args, options = {}) {
+  try {
+    if (!args || Object.keys(args).sort().join(',') !== 'business,owner,reason,root,run' ||
+        typeof args.root !== 'string' || typeof args.business !== 'string' || !ID.test(args.business) ||
+        typeof args.run !== 'string' || !ID.test(args.run) ||
+        !args.owner || typeof args.owner !== 'object' || Array.isArray(args.owner)) fail();
+    if (args.reason === 'fire') {
+      if (Object.keys(args.owner).join(',') !== 'decision' || typeof args.owner.decision !== 'string' || !ID.test(args.owner.decision)) fail();
+    } else if (args.reason === 'kill-switch') {
+      if (Object.keys(args.owner).join(',') !== 'generation' || !UUID.test(args.owner.generation)) fail();
+      const state = readControl(args.root);
+      if (!state.halted || state.generation !== args.owner.generation) throw new ProcessingError('processing-generation-changed');
+    } else fail();
+    const root = rootTag(args.root), key = stopKey(args.root, args.business, args.run);
+    const local = root + ':' + key;
+    if (stopping.has(local)) return stopping.get(local);
+    const pending = Promise.resolve().then(() => ownStop({ ...args, rootHash: root }, key, options)).catch(e => {
+      if (!e.code?.startsWith('processing-')) throw e;
+      return { run: args.run, outcome: 'unknown', pid: null, signals: [], receipt: null };
+    });
+    stopping.set(local, pending);
+    pending.then(() => stopping.delete(local), () => stopping.delete(local));
+    return pending;
+  } catch (e) { return Promise.reject(e); }
+}
+async function ownStop(args, key, options) {
+  const { root, rootHash, business, run, reason, owner } = args;
+  const files = stopPaths(root, key), expected = { root: rootHash, business, run };
+  const old = optionalRead(files.result);
+  if (old) return stopResult(old, expected);
+  const now = options.now ?? Date.now, sleep = options.sleep ?? wait;
+  const grace = options.graceMs ?? STOP_GRACE_MS, observe = options.killWaitMs ?? STOP_OBSERVE_MS;
+  const started = now();
+  const claim = { version: 1, id: randomUUID(), ...expected, reason, owner,
+    supervisor: processIdentity(process.pid), at: new Date().toISOString(), deadline: Date.now() + grace + observe };
+  const winner = write(files.claim, claim, true);
+  if (winner.root !== rootHash || winner.business !== business || winner.run !== run || !UUID.test(winner.id) ||
+      !Number.isFinite(winner.deadline) || winner.deadline > Date.now() + STOP_GRACE_MS + STOP_OBSERVE_MS + 1000) fail();
+  if (winner.id !== claim.id) {
+    // Another host owns delivery. No lease stealing or fresh deadlines on owner loss.
+    while (Date.now() <= winner.deadline) {
+      const result = optionalRead(files.result);
+      if (result) return stopResult(result, expected);
+      if (alive(winner.supervisor) !== true) break;
+      await sleep(20);
+    }
+    return { run, outcome: 'unknown', pid: null, signals: [], receipt: null };
+  }
+  let record = null, signals = [], initialIdentity = null;
+  const finish = outcome => {
+    const doc = { version: 1, id: claim.id, ...expected, reason, owner, at: new Date().toISOString(),
+      runtime: record?.id ?? null, kind: record?.kind ?? null, outcome, signals: [...signals],
+      identity: initialIdentity };
+    return stopResult(write(files.result, doc, true), expected);
+  };
+  const matches = listRuntimes(root).filter(r => r.business === business && r.run === run);
+  if (matches.length !== 1) return finish('unknown');
+  record = matches[0];
+  if (reason === 'kill-switch') record = updateRuntime(root, record.id, { haltGeneration: owner.generation });
+  if (record.pid) initialIdentity = { pid: record.pid, startTime: record.startTime, boot: record.boot };
+  if (record.containerName) {
+    let containerStop = options.containerStop;
+    if (!containerStop) {
+      const { createContainerStopper } = await import('./containers.mjs');
+      containerStop = createContainerStopper({ dataRoot: root });
+    }
+    const result = await containerStop(record, { graceMs: grace, killWaitMs: observe });
+    signals = result.signals;
+    return finish(result.outcome === 'killed' ? 'killed' :
+      ['terminated','already-exited'].includes(result.outcome) ? 'stopped' : 'unknown');
+  }
+  const identity = options.identity ?? processIdentity;
+  let members = record.group && alive(record) === true && groupOf(record.pid) === record.pid
+    ? groupMembers(record.pid) : record.members ?? [];
+  const status = r => {
+    if (!r.pid) return r.phase === 'ended' ? false : null;
+    const current = identity(r.pid);
+    if (current && (current.pid !== r.pid || current.startTime !== r.startTime || current.boot !== r.boot))
+      return 'identity-changed';
+    if (initialIdentity && (initialIdentity.pid !== r.pid || initialIdentity.startTime !== r.startTime || initialIdentity.boot !== r.boot))
+      return 'identity-changed';
+    if (options.state) {
+      const observed = options.state(r);
+      return observed === true && !current && !r.group ? null : observed;
+    }
+    return runtimeGroupState({ ...r, members });
+  };
+  const deliver = (r, sig) => {
+    // Re-check immediately before the actual signal, including fixture delivery.
+    if (status(r) !== true) return false;
+    if (r.group) updateRuntime(root, r.id, { members: members.slice(0,64) });
+    return options.signal ? options.signal(r, sig) : signal(r, sig, members);
+  };
+  const termEnd = started + grace, deadline = termEnd + observe;
+  let termTried = false, killTried = false;
+  while (now() <= deadline) {
+    try { record = runtime(root, record.id); }
+    catch {
+      const present = readdirSync(directory(root, 'runtimes')).includes(record.id + '.json');
+      return finish(present ? 'unknown' : signals.includes('SIGKILL') ? 'killed' : 'stopped');
+    }
+    if (!initialIdentity && record.pid) initialIdentity = { pid: record.pid, startTime: record.startTime, boot: record.boot };
+    if (record.group && members.some(m => alive(m) === true && groupOf(m.pid) === record.pid)) {
+      const found = groupMembers(record.pid);
+      members = [...members, ...found.filter(m => !members.some(old => old.pid === m.pid && old.startTime === m.startTime))];
+    }
+    let live = status(record);
+    if (live === 'identity-changed') return finish('identity-changed');
+    if ((record.phase === 'ended' && !record.group) || live === false)
+      return finish(signals.includes('SIGKILL') ? 'killed' : 'stopped');
+    if (record.pid && live === true && !termTried) {
+      termTried = true;
+      if (deliver(record, 'SIGTERM')) signals.push('SIGTERM');
+    }
+    if (record.pid && live === true && now() >= termEnd && !killTried) {
+      killTried = true;
+      if (deliver(record, 'SIGKILL')) signals.push('SIGKILL');
+    }
+    if (now() >= deadline) {
+      live = status(record);
+      return finish(live === 'identity-changed' ? 'identity-changed' : live === true ? 'alive' :
+        live === false ? signals.includes('SIGKILL') ? 'killed' : 'stopped' : 'unknown');
+    }
+    await sleep(Math.min(20, Math.max(1, deadline - now())));
+  }
+  return finish('unknown');
+}
+
+// A later exit is new evidence, never a replacement for a fire caller's first result.
+function laterExit(root, first, receipt, generation) {
+  try {
+    const current = runtime(root, first.id);
+    if (current.pid) {
+      const identity = processIdentity(current.pid);
+      if (identity && (identity.startTime !== current.startTime || identity.boot !== current.boot)) return false;
+      if (runtimeGroupState(current) !== false) return false;
+    } else if (current.phase !== 'ended') return false;
+    const key = stopKey(root, first.business, first.run);
+    write(join(directory(root, 'run-stops'), key + '.' + generation + '.observation.json'), {
+      version: 1, id: randomUUID(), stop: receipt.id, generation, runtime: first.id,
+      root: rootTag(root), business: first.business, run: first.run, outcome: 'exited', at: new Date().toISOString(),
+    }, true);
+    return true;
+  } catch { return false; }
+}
+
+export async function sweepRuntimes(root, generation, { graceMs = 5000, killWaitMs = 2000, containerStop = null,
+  beforeStop = () => {}, stopOptions = {} } = {}) {
+  const state = readControl(root);
+  if (!state.halted || state.generation !== generation) throw new ProcessingError('processing-generation-changed');
+  const prior = readStops(root, generation);
+  const results = await Promise.all(listRuntimes(root).map(async first => {
+    const complete = prior.find(s => s.runtime === first.id && s.outcome !== 'unknown');
+    if (complete) return complete;
+    let problem = null;
+    try { await beforeStop(first, generation); } catch { problem = 'brake-unconfirmed'; }
+    const result = await stopRun({ root, business: first.business, run: first.run,
+      reason: 'kill-switch', owner: { generation } }, { graceMs, killWaitMs, containerStop, ...stopOptions });
+    let outcome = result.outcome === 'stopped' ? 'terminated' : result.outcome === 'killed' ? 'killed' : 'unknown';
+    if (outcome === 'unknown' && result.receipt && !problem && laterExit(root, first, result.receipt, generation))
+      outcome = 'terminated';
+    if (problem) outcome = 'unknown';
+    return stopRecord(root, generation, first, outcome, result.signals, problem, result.receipt);
+
+  }));
+  const remaining = results.filter(r => r.outcome === 'unknown').length;
+  return { quiescent: remaining === 0, remaining, stopped: results.length - remaining, results };
+}

packages/processing-control/src/state.mjs

@@ -0,0 +1,129 @@
+// Host-owned, per-data-root admission state. No model, git or credential imports.
+import { randomUUID } from 'node:crypto';
+import { constants, closeSync, fstatSync, fsyncSync, lstatSync, mkdirSync, openSync, readSync, realpathSync,
+  renameSync, unlinkSync, writeFileSync } from 'node:fs';
+import { join } from 'node:path';
+
+export class ProcessingError extends Error {
+  constructor(code) { super(code); this.name = 'ProcessingError'; this.code = code; }
+}
+const fail = code => { throw new ProcessingError(code); };
+const UUID = /^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/;
+const ID = /^[a-zA-Z0-9][a-zA-Z0-9_.:@/-]{0,159}$/;
+const identity = value => typeof value === 'string' && ID.test(value);
+const FIELDS = ['version', 'generation', 'operation', 'halted', 'at', 'business', 'human', 'recovered'];
+const MAX_BYTES = 8192;
+
+export function controlDirectory(dataRoot) {
+  try {
+    const root = realpathSync(dataRoot), st = lstatSync(root);
+    if (!st.isDirectory() || st.uid !== process.getuid()) fail('processing-control-unsafe');
+    return join(root, 'control');
+  } catch { fail('processing-control-unsafe'); }
+}
+function parent(dataRoot) {
+  const dir = controlDirectory(dataRoot);
+  let st;
+  try { st = lstatSync(dir); }
+  catch (e) {
+    if (e.code === 'ENOENT') fail('processing-uninitialized');
+    fail('processing-control-unsafe');
+  }
+  if (!st.isDirectory() || st.isSymbolicLink() || st.uid !== process.getuid() || (st.mode & 0o7777) !== 0o700)
+    fail('processing-control-unsafe');
+  return dir;
+}
+function valid(doc) {
+  if (!doc || typeof doc !== 'object' || Array.isArray(doc) ||
+      Object.keys(doc).length !== FIELDS.length || Object.keys(doc).some(k => !FIELDS.includes(k)) ||
+      doc.version !== 1 || !UUID.test(doc.generation) || typeof doc.halted !== 'boolean' ||
+      typeof doc.recovered !== 'boolean' || typeof doc.at !== 'string' ||
+      !Number.isFinite(Date.parse(doc.at)) || new Date(doc.at).toISOString() !== doc.at)
+    fail('processing-state-invalid');
+  if (doc.operation === null) {
+    if (doc.halted || doc.business !== null || doc.human !== null || doc.recovered) fail('processing-state-invalid');
+  } else if (!UUID.test(doc.operation) || !identity(doc.business) || !identity(doc.human)) fail('processing-state-invalid');
+  return Object.freeze(doc);
+}
+export function readControl(dataRoot) {
+  const file = join(parent(dataRoot), 'processing.json');
+  let fd;
+  try {
+    fd = openSync(file, constants.O_RDONLY | constants.O_NOFOLLOW | constants.O_NONBLOCK);
+    const st = fstatSync(fd);
+    if (!st.isFile() || st.uid !== process.getuid() || (st.mode & 0o7777) !== 0o600 || st.size > MAX_BYTES)
+      fail('processing-state-invalid');
+    const buf = Buffer.alloc(MAX_BYTES + 1);
+    let size = 0, n;
+    while ((n = readSync(fd, buf, size, buf.length - size, null)) > 0) {
+      size += n;
+      if (size > MAX_BYTES) fail('processing-state-invalid');
+    }
+    return valid(JSON.parse(new TextDecoder('utf-8', { fatal: true }).decode(buf.subarray(0, size))));
+  } catch { fail('processing-state-invalid'); }
+  finally { if (fd !== undefined) closeSync(fd); }
+}
+function publish(dataRoot, doc) {
+  const dir = parent(dataRoot), file = join(dir, 'processing.json'), temp = join(dir, `.state-${randomUUID()}`);
+  let fd, dirfd;
+  try {
+    fd = openSync(temp, constants.O_WRONLY | constants.O_CREAT | constants.O_EXCL | constants.O_NOFOLLOW, 0o600);
+    writeFileSync(fd, JSON.stringify(valid(doc)) + '\n');
+    fsyncSync(fd); closeSync(fd); fd = undefined;
+    renameSync(temp, file);
+    dirfd = openSync(dir, constants.O_RDONLY | constants.O_DIRECTORY | constants.O_NOFOLLOW);
+    fsyncSync(dirfd);
+  } catch { fail('processing-state-invalid'); }
+  finally {
+    if (fd !== undefined) closeSync(fd);
+    if (dirfd !== undefined) closeSync(dirfd);
+    try { unlinkSync(temp); } catch (e) { if (e.code !== 'ENOENT') fail('processing-state-invalid'); }
+  }
+}
+
+// First-use host bootstrap only. A present directory with no file is not a new installation.
+export function initializeControl(dataRoot) {
+  const dir = controlDirectory(dataRoot);
+  try { mkdirSync(dir, { mode: 0o700 }); }
+  catch (e) {
+    if (e.code === 'EEXIST') return readControl(dataRoot);
+    fail('processing-control-unsafe');
+  }
+  const rootfd = openSync(realpathSync(dataRoot), constants.O_RDONLY | constants.O_DIRECTORY | constants.O_NOFOLLOW);
+  try { fsyncSync(rootfd); } finally { closeSync(rootfd); }
+  publish(dataRoot, { version: 1, generation: randomUUID(), operation: null, halted: false,
+    at: new Date().toISOString(), business: null, human: null, recovered: false });
+  return readControl(dataRoot);
+}
+export function assertProcessing(dataRoot, generation = null) {
+  const state = readControl(dataRoot);
+  if (state.halted) fail('processing-halted');
+  if (generation !== null && state.generation !== generation) fail('processing-generation-changed');
+  return state;
+}
+
+// Called only by the coordinator after the broker has proved a human.
+export function transition(dataRoot, { halted, business, human, generation = null }) {
+  if (typeof halted !== 'boolean' || !identity(business) || !identity(human)) fail('invalid-request');
+  parent(dataRoot);
+  let current, recovered = false;
+  try { current = readControl(dataRoot); }
+  catch (e) {
+    if (!halted || e.code !== 'processing-state-invalid') throw e;
+    recovered = true;
+  }
+  if (!halted && generation !== current.generation) fail('processing-generation-changed');
+  if (current?.halted === halted) return { ...current, changed: false };
+  const operation = randomUUID();
+  const state = { version: 1, generation: operation, operation, halted,
+    at: new Date().toISOString(), business, human, recovered };
+  publish(dataRoot, state);
+  return { ...state, changed: true };
+}
+export function processingStatus(dataRoot) {
+  try { return readControl(dataRoot); }
+  catch (e) {
+    if (!(e instanceof ProcessingError)) throw e;
+    return { halted: e.code === 'processing-uninitialized' ? null : true, invalid: true, code: e.code };
+  }
+}

packages/processing-control/tests/containers.test.mjs

@@ -0,0 +1,85 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { mkdtempSync, rmSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { initializeControl, transition } from '../src/state.mjs';
+const api = await import('../src/containers.mjs').catch(e => { if (e.code === 'ERR_MODULE_NOT_FOUND') return {}; throw e; });
+function fixture(t) { const root = mkdtempSync(join(tmpdir(), 'processing-container-')); initializeControl(root); t.after(() => rmSync(root, { recursive: true, force: true })); return root; }
+const actor = { business: 'demo', human: 'jason', halted: true };
+test('container admission publishes its generated name and root/runtime labels before dispatch', t => {
+  assert.equal(typeof api.prepareContainer, 'function');
+  const root = fixture(t), r = api.prepareContainer(root, { kind: 'task', business: 'instance', run: 'run-1' });
+  const args = api.containerArgs(r, { args: ['request'] });
+  assert.match(r.containerName, /^mosaic-[a-f0-9]{12}-[a-f0-9-]{36}$/);
+  assert.ok(args.includes(r.containerName)); assert.ok(args.includes(`mosaic.root=${r.root}`));
+  assert.ok(args.includes(`mosaic.runtime=${r.id}`)); assert.ok(args.includes(`MOSAIC_PROCESSING_GENERATION=${r.generation}`));
+  assert.deepEqual(args.slice(-2), ['mosaic-agent', 'request']);
+  transition(root, actor); assert.throws(() => api.prepareContainer(root, { kind: 'task', business: 'instance', run: 'new' }), e => e.code === 'processing-halted');
+});
+function inspected(r, running = true, id = 'a'.repeat(64)) {
+  return { Id: id, Name: '/' + r.containerName, Config: { Labels: { 'mosaic.root': r.root, 'mosaic.runtime': r.id } }, State: { Running: running } };
+}
+test('container sweep sends TERM then KILL only after verifying exact id and both labels', async t => {
+  assert.equal(typeof api.createContainerStopper, 'function');
+  const root = fixture(t), r = api.prepareContainer(root, { kind: 'task', business: 'instance', run: 'one' });
+  const calls = []; let running = true;
+  const stop = api.createContainerStopper({ docker: async args => {
+    calls.push(args);
+    if (args[0] === 'inspect') return JSON.stringify(inspected(r, running));
+    if (args.includes('KILL')) running = false;
+    return '';
+  } });
+  const result = await stop(r, { graceMs: 30, killWaitMs: 100 });
+  assert.equal(result.outcome, 'killed'); assert.deepEqual(result.signals, ['SIGTERM', 'SIGKILL']);
+  assert.deepEqual(calls.filter(c => c[0] === 'kill'), [['kill', '--signal', 'TERM', 'a'.repeat(64)], ['kill', '--signal', 'KILL', 'a'.repeat(64)]]);
+});
+test('foreign labels and a replaced container id stay unknown and are never signalled', async t => {
+  assert.equal(typeof api.createContainerStopper, 'function');
+  const root = fixture(t), r = api.prepareContainer(root, { kind: 'task', business: 'instance', run: 'one' });
+  const calls = [];
+  const stop = api.createContainerStopper({ docker: async args => {
+    calls.push(args); const doc = inspected(r); doc.Config.Labels['mosaic.root'] = 'b'.repeat(64); return JSON.stringify(doc);
+  } });
+  assert.equal((await stop(r, { graceMs: 1, killWaitMs: 1 })).outcome, 'unknown');
+  assert.equal(calls.filter(c => c[0] === 'kill').length, 0);
+  let reads = 0; calls.length = 0;
+  const replacement = api.createContainerStopper({ docker: async args => {
+    calls.push(args); if (args[0] !== 'inspect') return '';
+    return JSON.stringify(inspected(r, true, (++reads > 1 ? 'b' : 'a').repeat(64)));
+  } });
+  assert.equal((await replacement(r, { graceMs: 1, killWaitMs: 1 })).outcome, 'unknown');
+  assert.equal(calls.filter(c => c[0] === 'kill').length, 0);
+});
+test('an unverified missing container remains unknown rather than claiming a pending start ended', async t => {
+  assert.equal(typeof api.createContainerStopper, 'function');
+  const root = fixture(t), r = api.prepareContainer(root, { kind: 'container', business: 'instance', run: 'one' });
+  const stop = api.createContainerStopper({ docker: async () => { throw new Error('no container'); } });
+  assert.equal((await stop(r, { graceMs: 5, killWaitMs: 5 })).outcome, 'unknown');
+});
+
+test('a removed --rm container is settled only by its trusted owner completion receipt', async t => {
+  const { updateRuntime } = await import('../src/runtimes.mjs');
+  const root = fixture(t), r = api.prepareContainer(root, { kind: 'task', business: 'instance', run: 'one' });
+  let removed = false;
+  const stop = api.createContainerStopper({ dataRoot: root, docker: async args => {
+    if (args[0] === 'kill') { removed = true; updateRuntime(root, r.id, { phase: 'ended' }); return ''; }
+    if (removed) throw Error('removed by --rm');
+    return JSON.stringify(inspected(r));
+  } });
+  const result = await stop(r, { graceMs: 30, killWaitMs: 100 });
+  assert.equal(result.outcome, 'terminated'); assert.deepEqual(result.signals, ['SIGTERM']);
+});
+
+test('after signalling a verified container, successful empty Docker listing proves --rm removed that id', async t => {
+  const root = fixture(t), r = api.prepareContainer(root, { kind: 'task', business: 'instance', run: 'one' });
+  let removed = false;
+  const stop = api.createContainerStopper({ docker: async args => {
+    if (args[0] === 'kill') { removed = true; return ''; }
+    if (args[0] === 'ps') return '';
+    if (removed) throw Error('removed');
+    return JSON.stringify(inspected(r));
+  } });
+  const result = await stop(r, { graceMs: 20, killWaitMs: 100 });
+  assert.equal(result.outcome, 'terminated'); assert.deepEqual(result.signals, ['SIGTERM']);
+});

packages/processing-control/tests/coordinator.test.mjs

@@ -0,0 +1,67 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { spawn } from 'node:child_process';
+import { once } from 'node:events';
+import { mkdtempSync, rmSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { readControl, assertProcessing } from '../src/state.mjs';
+import { registerRuntime, updateRuntime, processIdentity, unregisterRuntime } from '../src/runtimes.mjs';
+const { createProcessing } = await import('../src/coordinator.mjs').catch(e => { if (e.code === 'ERR_MODULE_NOT_FOUND') return {}; throw e; });
+const actor = { business: 'demo', human: 'jason' };
+function fixture(t) {
+  assert.equal(typeof createProcessing, 'function');
+  const root = mkdtempSync(join(tmpdir(), 'processing-coordinator-'));
+  const c = createProcessing({ dataRoot: root, graceMs: 80, killWaitMs: 1000 });
+  t.after(async () => { await c.close(); rmSync(root, { recursive: true, force: true }); });
+  return { root, c };
+}
+
+test('halt publishes before awaiting stops, resume refuses pending, and only clear permits new work', async t => {
+  const { root, c } = fixture(t);
+  const p = spawn(process.execPath, ['-e', "process.on('SIGTERM',()=>{});console.log('ready');setInterval(()=>{},1000)"], { detached: true, stdio: ['ignore', 'pipe', 'ignore'] });
+  const exit = once(p, 'exit');
+  t.after(async () => { if (p.signalCode === null && p.exitCode === null) { try { process.kill(-p.pid, 'SIGKILL'); } catch {} await exit; } });
+  await once(p.stdout, 'data');
+  const r = registerRuntime(root, { business: 'demo', run: 'standin', kind: 'session' });
+  updateRuntime(root, r.id, { ...processIdentity(p.pid), group: true, phase: 'running' });
+  const halted = c.halt(actor);
+  assert.equal(readControl(root).halted, true, 'durable gate is set before any stop await');
+  await assert.rejects(c.resume({ ...actor, generation: readControl(root).generation }), { code: 'processing-stop-pending' });
+  const result = await halted;
+  assert.equal(result.quiescent, true);
+  assert.deepEqual(await exit, [null, 'SIGKILL']);
+  assert.throws(() => assertProcessing(root), { code: 'processing-halted' });
+  const resumed = await c.resume({ ...actor, generation: result.generation });
+  assert.equal(resumed.halted, false);
+  assert.doesNotThrow(() => assertProcessing(root));
+});
+
+test('a new coordinator replays a persisted halt and an unresolved start keeps clear refused', async t => {
+  const { root, c } = fixture(t);
+  const pending = registerRuntime(root, { business: 'demo', run: 'starting', kind: 'session' });
+  const result = await c.halt(actor);
+  assert.equal(result.quiescent, false);
+  await c.close();
+  const next = createProcessing({ dataRoot: root, graceMs: 10, killWaitMs: 10 });
+  try {
+    assert.equal(next.read().halted, true);
+    await assert.rejects(next.resume({ ...actor, generation: result.generation }), { code: 'processing-stop-pending' });
+    unregisterRuntime(root, pending.id);
+    const resumed = await next.resume({ ...actor, generation: result.generation });
+    assert.equal(resumed.halted, false);
+  } finally { await next.close(); }
+});
+
+test('a new halt generation never inherits a previous quiescent status before its sweep', async t => {
+  const { mkdtempSync, rmSync } = await import('node:fs');
+  const { tmpdir } = await import('node:os');
+  const { join } = await import('node:path');
+  const { transition } = await import('../src/state.mjs');
+  const root = mkdtempSync(join(tmpdir(), 'processing-counts-'));
+  const processing = createProcessing({ dataRoot: root });
+  t.after(async () => { await processing.close(); rmSync(root, { recursive: true, force: true }); });
+  transition(root, { business: 'demo', human: 'jason', halted: true });
+  assert.equal(processing.read().quiescent, false);
+  await processing.reconcile(); assert.equal(processing.read().quiescent, true);
+});

packages/processing-control/tests/effects.test.mjs

@@ -0,0 +1,74 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { spawn } from 'node:child_process';
+import { once } from 'node:events';
+import { mkdtempSync, rmSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { initializeControl, transition } from '../src/state.mjs';
+const api = await import('../src/effects.mjs').catch(e => { if (e.code === 'ERR_MODULE_NOT_FOUND') return {}; throw e; });
+function fixture(t) { const root = mkdtempSync(join(tmpdir(), 'processing-effect-')); initializeControl(root); t.after(() => rmSync(root, { recursive: true, force: true })); return root; }
+const actor = { business: 'demo', human: 'jason', halted: true };
+test('halt aborts an active local request and prevents a subsequent effect after halt/resume', async t => {
+  assert.equal(typeof api.withProcessing, 'function');
+  const root = fixture(t); let started;
+  const ready = new Promise(resolve => { started = resolve; });
+  const work = api.withProcessing(root, async scope => {
+    await new Promise(resolve => { scope.signal.addEventListener('abort', resolve, { once: true }); started(); });
+    scope.guard();
+  });
+  await ready; const halted = transition(root, actor);
+  transition(root, { ...actor, halted: false, generation: halted.generation });
+  await assert.rejects(work, e => e.code === 'processing-generation-changed');
+});
+test('processing scopes isolate roots and cancel only the registered child group', async t => {
+  assert.equal(typeof api.withProcessing, 'function');
+  const a = fixture(t), b = fixture(t);
+  let admitted;
+  const ready = new Promise(resolve => { admitted = resolve; });
+  const task = api.withProcessing(a, async scope => {
+    const child = spawn(process.execPath, ['-e', "process.on('SIGTERM',()=>process.exit(0));console.log('ready');setInterval(()=>{},1000)"], { detached: true, stdio: ['ignore', 'pipe', 'pipe'] });
+    const exit = once(child, 'exit'); t.after(() => { try { process.kill(-child.pid, 'SIGKILL'); } catch {} });
+    scope.track(child); await once(child.stdout, 'data'); admitted();
+    const outcome = await exit; assert.deepEqual(outcome, [0, null]); scope.guard();
+  });
+  await ready; transition(b, actor);
+  await api.withProcessing(a, async scope => scope.guard());
+  transition(a, actor);
+  await assert.rejects(task, e => e.code === 'processing-halted');
+});
+test('halted scopes never invoke their body and unscoped human work has no processing context', async t => {
+  assert.equal(typeof api.withProcessing, 'function');
+  const root = fixture(t); transition(root, actor); let called = false;
+  await assert.rejects(api.withProcessing(root, async () => { called = true; }), e => e.code === 'processing-halted');
+  assert.equal(called, false); assert.equal(api.currentProcessing(), undefined);
+});
+
+test('host git is stopped promptly by the active scope rather than waiting for its long deadline', async t => {
+  const { mkdirSync, writeFileSync } = await import('node:fs');
+  const { runGit, gitEnv } = await import('../../seat/src/checkout.mjs');
+  const root = fixture(t), bin = join(root, 'bin'); mkdirSync(bin);
+  writeFileSync(join(bin, 'git'), `#!${process.execPath}\nprocess.on('SIGTERM',()=>process.exit(0));setInterval(()=>{},1000);\n`, { mode: 0o755 });
+  const begin = Date.now();
+  const task = api.withProcessing(root, async () => runGit(['status'], { ...gitEnv(), PATH: bin + ':' + process.env.PATH }, { timeoutMs: 10000, graceMs: 100 }));
+  await new Promise(resolve => setTimeout(resolve, 100)); transition(root, actor);
+  await assert.rejects(task, e => e.code === 'processing-halted');
+  assert.ok(Date.now() - begin < 2000, 'the halt cancels the actual git process');
+});
+
+test('a child leader exiting does not erase an unverified surviving group receipt', async t => {
+  const { listRuntimes } = await import('../src/runtimes.mjs');
+  const root = fixture(t);
+  let child;
+  await api.withProcessing(root, async scope => {
+    const script = `const {spawn}=require('node:child_process');spawn(process.execPath,['-e','setInterval(()=>{},1000)'],{stdio:'ignore'});console.log('ready');setTimeout(()=>process.exit(0),80);`;
+    child = spawn(process.execPath, ['-e', script], { detached: true, stdio: ['ignore', 'pipe', 'pipe'] });
+    t.after(() => { try { process.kill(-child.pid, 'SIGKILL'); } catch {} });
+    const closed = once(child, 'close');
+    scope.track(child); await once(child.stdout, 'data'); await closed;
+  });
+  const records = listRuntimes(root);
+  assert.equal(records.length, 1, 'unknown group remains discoverable to the independent halt sweep');
+  assert.equal(records[0].pid, child.pid);
+  assert.equal(records[0].group, true);
+});

packages/processing-control/tests/mount.test.mjs

@@ -0,0 +1,36 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { spawnSync } from 'node:child_process';
+import { mkdtempSync, readFileSync, rmSync, statSync, writeFileSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { initializeControl, transition } from '../src/state.mjs';
+import { sandboxProblem } from '../../seat/src/sandbox.mjs';
+const skip = sandboxProblem() ?? false;
+test('the actual nested read-only control mount refuses unlink, replacement and parent removal', { skip }, t => {
+  const root = mkdtempSync(join(tmpdir(), 'processing-mount-'));
+  t.after(() => rmSync(root, { recursive: true, force: true }));
+  initializeControl(root); transition(root, { business: 'demo', human: 'jason', halted: true });
+  const file = join(root, 'control', 'processing.json'), bytes = readFileSync(file), inode = statSync(file).ino;
+  writeFileSync(join(root, 'replacement'), 'off replacement');
+  const r = spawnSync('bwrap', ['--unshare-user', '--unshare-pid', '--die-with-parent',
+    '--ro-bind', '/usr', '/usr', '--symlink', 'usr/bin', '/bin', '--symlink', 'usr/lib', '/lib',
+    '--symlink', 'usr/lib64', '/lib64', '--proc', '/proc', '--dev', '/dev',
+    '--bind', root, '/fixture', '--ro-bind', join(root, 'control'), '/fixture/control',
+    '/bin/sh', '-c', 'rm /fixture/control/processing.json && exit 10; echo unlink-refused; mv /fixture/replacement /fixture/control/processing.json && exit 11; echo replace-refused; rm -rf /fixture/control && exit 12; echo parent-refused'],
+    { encoding: 'utf8', timeout: 5000 });
+  assert.equal(r.status, 0, r.stderr);
+  assert.match(r.stdout, /unlink-refused/); assert.match(r.stdout, /replace-refused/); assert.match(r.stdout, /parent-refused/);
+  assert.deepEqual(readFileSync(file), bytes); assert.equal(statSync(file).ino, inode);
+});
+test('the image entrypoint refuses halted and stale generations using the shared reader', t => {
+  const root = mkdtempSync(join(tmpdir(), 'processing-entry-'));
+  t.after(() => rmSync(root, { recursive: true, force: true }));
+  const initial = initializeControl(root), entry = new URL('../src/entrypoint.mjs', import.meta.url).pathname;
+  const run = generation => spawnSync(process.execPath, [entry, root], { env: { ...process.env, MOSAIC_PROCESSING_GENERATION: generation }, encoding: 'utf8' });
+  assert.equal(run(initial.generation).status, 0);
+  const halt = transition(root, { business: 'demo', human: 'jason', halted: true });
+  assert.equal(run(initial.generation).status, 3);
+  transition(root, { business: 'demo', human: 'jason', halted: false, generation: halt.generation });
+  const stale = run(initial.generation); assert.equal(stale.status, 3); assert.match(stale.stderr, /processing-generation-changed/);
+});

packages/processing-control/tests/runtimes.test.mjs

@@ -0,0 +1,183 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { spawn, spawnSync } from 'node:child_process';
+import { existsSync, mkdtempSync, readFileSync, rmSync, writeFileSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { once } from 'node:events';
+import { initializeControl, transition } from '../src/state.mjs';
+const api = await import('../src/runtimes.mjs').catch(e => { if (e.code === 'ERR_MODULE_NOT_FOUND') return {}; throw e; });
+const actor = { business: 'demo', human: 'jason', halted: true };
+const delay = ms => new Promise(resolve => setTimeout(resolve, ms));
+function fixture(t) {
+  const root = mkdtempSync(join(tmpdir(), 'processing-runtime-'));
+  initializeControl(root); t.after(() => rmSync(root, { recursive: true, force: true }));
+  return root;
+}
+async function child(t, stubborn = false) {
+  const p = spawn(process.execPath, ['-e', `process.on('SIGTERM',()=>{${stubborn ? '' : 'process.exit(0)'}});console.log('ready');setInterval(()=>{},1000)`], { detached: true, stdio: ['ignore', 'pipe', 'pipe'] });
+  const ended = once(p, 'exit');
+  t.after(async () => { if (p.exitCode === null && p.signalCode === null) { try { process.kill(-p.pid, 'SIGKILL'); } catch {} await ended; } });
+  await once(p.stdout, 'data');
+  return { p, ended };
+}
+function receipt(root, p) {
+  const r = api.registerRuntime(root, { kind: 'session', business: 'demo', run: 'run' });
+  return api.updateRuntime(root, r.id, { ...api.processIdentity(p.pid), phase: 'running', group: true });
+}
+
+// Without TERM, a cooperative child would survive until unnecessary escalation.
+test('halt terminates a tracked stand-in and leaves honest write-once stop evidence', async t => {
+  assert.equal(typeof api.registerRuntime, 'function');
+  const root = fixture(t), { p, ended } = await child(t);
+  const r = receipt(root, p);
+  const evidence = join(root, 'evidence.json'); writeFileSync(evidence, 'immutable existing result');
+  const state = transition(root, actor);
+  const result = await api.sweepRuntimes(root, state.generation, { graceMs: 150, killWaitMs: 1000 });
+  assert.equal(result.quiescent, true);
+  assert.equal(result.remaining, 0);
+  assert.deepEqual(await ended, [0, null]);
+  const stops = api.readStops(root, state.generation);
+  assert.equal(stops.length, 1);
+  assert.equal(stops[0].runtime, r.id);
+  assert.equal(stops[0].outcome, 'terminated');
+  assert.deepEqual(stops[0].signals, ['SIGTERM']);
+  assert.equal(readFileSync(evidence, 'utf8'), 'immutable existing result');
+  const bytes = JSON.stringify(stops);
+  await api.sweepRuntimes(root, state.generation, { graceMs: 10, killWaitMs: 1000 });
+  assert.equal(JSON.stringify(api.readStops(root, state.generation)), bytes);
+});
+
+// Dropping the KILL escalation leaves this actual child alive and fails quiescence.
+test('a TERM-resistant workload is killed after the bounded wait', async t => {
+  assert.equal(typeof api.registerRuntime, 'function');
+  const root = fixture(t), { p, ended } = await child(t, true);
+  receipt(root, p);
+  const state = transition(root, actor), begin = Date.now();
+  const result = await api.sweepRuntimes(root, state.generation, { graceMs: 80, killWaitMs: 1000 });
+  assert.equal(result.quiescent, true);
+  assert.deepEqual(await ended, [null, 'SIGKILL']);
+  assert.ok(Date.now() - begin >= 80);
+  assert.deepEqual(api.readStops(root, state.generation)[0].signals, ['SIGTERM', 'SIGKILL']);
+});
+
+// An unchecked stale start identity would terminate a different process.
+test('wrong start ticks or boot identity cannot signal a live replacement', async t => {
+  assert.equal(typeof api.registerRuntime, 'function');
+  const root = fixture(t), { p } = await child(t);
+  const r = receipt(root, p);
+  api.updateRuntime(root, r.id, { startTime: '0' });
+  const state = transition(root, actor);
+  await api.sweepRuntimes(root, state.generation, { graceMs: 30, killWaitMs: 30 });
+  await delay(30);
+  assert.equal(p.exitCode, null); assert.equal(p.signalCode, null);
+  assert.equal(api.readStops(root, state.generation)[0].outcome, 'unknown');
+});
+
+test('a pending start cannot be reported quiescent and a second root is never signalled', async t => {
+  assert.equal(typeof api.registerRuntime, 'function');
+  const a = fixture(t), b = fixture(t), { p } = await child(t);
+  api.registerRuntime(a, { kind: 'session', business: 'demo', run: 'pending' });
+  receipt(b, p);
+  const state = transition(a, actor);
+  const result = await api.sweepRuntimes(a, state.generation, { graceMs: 30, killWaitMs: 30 });
+  assert.equal(result.quiescent, false);
+  assert.equal(result.remaining, 1);
+  assert.equal(p.exitCode, null); assert.equal(p.signalCode, null);
+});
+
+// A group leader can exit on TERM while its child ignores it. Quiescence is the whole group.
+test('escalation still kills the tracked group after its leader exits', async t => {
+  const root = fixture(t);
+  const script = `const {spawn}=require('node:child_process');
+    const c=spawn(process.execPath,['-e',"process.on('SIGTERM',()=>{});console.log('ready');setInterval(()=>{},1000)"],{stdio:['ignore','pipe','inherit']});
+    c.stdout.once('data',()=>console.log(c.pid));process.on('SIGTERM',()=>process.exit(0));setInterval(()=>{},1000);`;
+  const p = spawn(process.execPath, ['-e', script], { detached: true, stdio: ['ignore', 'pipe', 'pipe'] });
+  t.after(() => { try { process.kill(-p.pid, 'SIGKILL'); } catch {} });
+  const [line] = await once(p.stdout, 'data');
+  const descendant = Number(String(line).trim());
+  const r = receipt(root, p), state = transition(root, actor);
+  const outcome = await api.sweepRuntimes(root, state.generation, { graceMs: 80, killWaitMs: 1000 });
+  assert.equal(outcome.quiescent, true);
+  assert.equal(api.processIdentity(descendant), null, 'stubborn descendant must not survive the group leader');
+  assert.equal(api.readStops(root, state.generation).find(s => s.runtime === r.id).outcome, 'killed');
+});
+
+// Session TERM goes to the runner, leaving the outer namespace for forced escalation.
+test('session TERM targets its verified runner before forcing the outer namespace', async t => {
+  const root = fixture(t);
+  const script = `const {spawn}=require('node:child_process');
+    process.on('SIGTERM',()=>require('node:fs').writeFileSync(${JSON.stringify(join(root, 'outer-term'))},'unexpected'));
+    const c=spawn(process.execPath,['-e',"process.on('SIGTERM',()=>process.exit(0));console.log('ready');setInterval(()=>{},1000)"],{stdio:['ignore','pipe','inherit']});
+    c.stdout.once('data',()=>console.log(c.pid));c.once('exit',()=>process.exit(0));setInterval(()=>{},1000);`;
+  const p = spawn(process.execPath, ['-e', script], { detached: true, stdio: ['ignore', 'pipe', 'pipe'] });
+  t.after(() => { try { process.kill(-p.pid, 'SIGKILL'); } catch {} });
+  const [line] = await once(p.stdout, 'data'), runner = api.processIdentity(Number(String(line).trim()));
+  const r = receipt(root, p);
+  api.updateRuntime(root, r.id, { runnerPid: runner.pid, runnerStartTime: runner.startTime });
+  const state = transition(root, actor);
+  const result = await api.sweepRuntimes(root, state.generation, { graceMs: 300, killWaitMs: 1000 });
+  assert.equal(result.quiescent, true);
+  assert.deepEqual(api.readStops(root, state.generation)[0].signals, ['SIGTERM']);
+  assert.equal(api.runtime(root, r.id).haltGeneration, state.generation);
+  assert.equal(existsSync(join(root, 'outer-term')), false);
+});
+
+// Publishing a receipt is not durable if its newly-created containing directory can vanish.
+test('new runtime and stop directories sync their containing directories', t => {
+  const root = fixture(t);
+  const script = `import fs from 'node:fs';import {syncBuiltinESMExports} from 'node:module';
+    const real=fs.fsyncSync,seen=[];fs.fsyncSync=fd=>{seen.push(fs.readlinkSync('/proc/self/fd/'+fd));return real(fd)};
+    syncBuiltinESMExports();const api=await import(process.argv[1]);
+    const {transition}=await import(process.argv[2]);
+    const r=api.registerRuntime(process.argv[3],{kind:'task',business:'demo',run:'gone'});
+    api.updateRuntime(process.argv[3],r.id,{phase:'ended'});
+    const s=transition(process.argv[3],{business:'demo',human:'jason',halted:true});
+    await api.sweepRuntimes(process.argv[3],s.generation);
+    console.log(JSON.stringify({seen,generation:s.generation}));`;
+  const child = spawnSync(process.execPath, ['--input-type=module', '-e', script,
+    new URL('../src/runtimes.mjs', import.meta.url).href, new URL('../src/state.mjs', import.meta.url).href, root], { encoding: 'utf8' });
+  assert.equal(child.status, 0, child.stderr);
+  const { seen, generation } = JSON.parse(child.stdout);
+  assert.ok(seen.filter(p => p === join(root, 'control')).length >= 3, 'runtime mkdir, halt rename and stops mkdir sync control');
+  assert.ok(seen.includes(join(root, 'control', 'stops')), 'generation directory creation syncs stops');
+  assert.ok(seen.includes(join(root, 'control', 'stops', generation)), 'stop receipt syncs generation directory');
+});
+
+test('a vanished group leader with unverified surviving members stays unknown, never quiescent', async t => {
+  const root = fixture(t);
+  const script = `const {spawn}=require('node:child_process');const c=spawn(process.execPath,['-e',"console.log('ready');setInterval(()=>{},1000)"],{stdio:['ignore','pipe','inherit']});c.stdout.once('data',()=>console.log(c.pid));process.on('SIGTERM',()=>process.exit(0));setInterval(()=>{},1000)`;
+  const p = spawn(process.execPath, ['-e', script], { detached: true, stdio: ['ignore', 'pipe', 'pipe'] });
+  t.after(() => { try { process.kill(-p.pid, 'SIGKILL'); } catch {} });
+  const [line] = await once(p.stdout, 'data'); const descendant = Number(String(line).trim());
+  receipt(root, p); const exited = once(p, 'exit'); p.kill('SIGTERM'); await exited;
+  const state = transition(root, actor);
+  const result = await api.sweepRuntimes(root, state.generation, { graceMs: 20, killWaitMs: 30 });
+  assert.equal(result.quiescent, false); assert.equal(result.remaining, 1);
+  assert.notEqual(api.processIdentity(descendant), null, 'never signal a group with no verified surviving anchor');
+});
+test('persisted member identity anchors a group after the leader exited before the sweep', async t => {
+  const root = fixture(t);
+  const script = `const {spawn}=require('node:child_process');const c=spawn(process.execPath,['-e',"process.on('SIGTERM',()=>{});console.log('ready');setInterval(()=>{},1000)"],{stdio:['ignore','pipe','inherit']});c.stdout.once('data',()=>console.log(c.pid));process.on('SIGTERM',()=>process.exit(0));setInterval(()=>{},1000)`;
+  const p = spawn(process.execPath, ['-e', script], { detached: true, stdio: ['ignore', 'pipe', 'pipe'] });
+  t.after(() => { try { process.kill(-p.pid, 'SIGKILL'); } catch {} });
+  const [line] = await once(p.stdout, 'data'), descendant = Number(String(line).trim()), r = receipt(root, p);
+  api.updateRuntime(root, r.id, { members: [api.processIdentity(descendant)] });
+  const exited = once(p, 'exit'); p.kill('SIGTERM'); await exited;
+  const state = transition(root, actor);
+  const result = await api.sweepRuntimes(root, state.generation, { graceMs: 30, killWaitMs: 1000 });
+  assert.equal(result.quiescent, true); assert.equal(api.processIdentity(descendant), null);
+  assert.deepEqual(api.readStops(root, state.generation)[0].signals, ['SIGTERM', 'SIGKILL']);
+});
+
+test('an unconfirmed secondary brake does not leave a verified workload running or claim success', async t => {
+  const root = fixture(t), { p, ended } = await child(t);
+  receipt(root, p); const state = transition(root, actor);
+  const result = await api.sweepRuntimes(root, state.generation, { graceMs: 60, killWaitMs: 1000,
+    beforeStop: () => { throw Error('fixture journal unavailable'); } });
+  await ended;
+  assert.equal(api.processIdentity(p.pid), null);
+  assert.equal(result.quiescent, false); assert.equal(result.remaining, 1);
+  const stops = api.readStops(root, state.generation); assert.equal(stops[0].outcome, 'unknown');
+  assert.equal(stops[0].problem, 'brake-unconfirmed');
+});

packages/processing-control/tests/state.test.mjs

@@ -0,0 +1,165 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { chmodSync, lstatSync, mkdirSync, mkdtempSync, readFileSync, rmSync, symlinkSync, unlinkSync, writeFileSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { spawnSync } from 'node:child_process';
+
+const api = await import('../src/state.mjs').catch(e => {
+  if (e.code === 'ERR_MODULE_NOT_FOUND') return {};
+  throw e;
+});
+const root = t => {
+  const dir = mkdtempSync(join(tmpdir(), 'processing-state-'));
+  t.after(() => rmSync(dir, { recursive: true, force: true }));
+  return dir;
+};
+const actor = { business: 'demo', human: 'jason' };
+const stateFile = dir => join(dir, 'control', 'processing.json');
+const refusal = code => e => e.code === code;
+
+// Removing durable publication must let a new reader launch after halt.
+test('halt persists across readers and resume needs the current generation', t => {
+  assert.equal(typeof api.initializeControl, 'function');
+  const dir = root(t);
+  const initial = api.initializeControl(dir);
+  assert.equal(initial.halted, false);
+  const halted = api.transition(dir, { ...actor, halted: true });
+  assert.equal(halted.halted, true);
+  assert.notEqual(halted.generation, initial.generation);
+  assert.equal(api.readControl(dir).generation, halted.generation);
+  assert.throws(() => api.assertProcessing(dir), refusal('processing-halted'));
+  assert.throws(() => api.transition(dir, { ...actor, halted: false, generation: initial.generation }), refusal('processing-generation-changed'));
+  const resumed = api.transition(dir, { ...actor, halted: false, generation: halted.generation });
+  assert.equal(resumed.halted, false);
+  assert.doesNotThrow(() => api.assertProcessing(dir));
+  // A start that waited across halt+resume must not use its old admission.
+  assert.throws(() => api.assertProcessing(dir, initial.generation), refusal('processing-generation-changed'));
+  assert.equal(lstatSync(stateFile(dir)).mode & 0o777, 0o600);
+  assert.equal(lstatSync(join(dir, 'control')).mode & 0o777, 0o700);
+});
+
+// Reinitializing a missing file as off would bypass a previously published halt.
+test('first initialization is explicit; missing state after control exists fails closed and halt repairs it', t => {
+  assert.equal(typeof api.initializeControl, 'function');
+  const dir = root(t);
+  assert.throws(() => api.readControl(dir), refusal('processing-uninitialized'));
+  const initial = api.initializeControl(dir);
+  assert.equal(api.initializeControl(dir).generation, initial.generation);
+  unlinkSync(stateFile(dir));
+  assert.throws(() => api.initializeControl(dir), refusal('processing-state-invalid'));
+  assert.throws(() => api.assertProcessing(dir), refusal('processing-state-invalid'));
+  assert.throws(() => api.transition(dir, { ...actor, halted: false, generation: initial.generation }), refusal('processing-state-invalid'));
+  const halted = api.transition(dir, { ...actor, halted: true });
+  assert.equal(halted.recovered, true);
+  assert.equal(halted.halted, true);
+  assert.equal(api.transition(dir, { ...actor, halted: false, generation: halted.generation }).halted, false);
+});
+
+// A read error, permissive mode or unbounded payload must never look like off.
+for (const [name, edit] of [
+  ['invalid JSON', file => writeFileSync(file, '{')],
+  ['unknown keys', file => writeFileSync(file, JSON.stringify({ ...JSON.parse(readFileSync(file)), extra: true }))],
+  ['bad timestamp', file => writeFileSync(file, JSON.stringify({ ...JSON.parse(readFileSync(file)), at: 'yesterday' }))],
+  ['nonboolean state', file => writeFileSync(file, JSON.stringify({ ...JSON.parse(readFileSync(file)), halted: 0 }))],
+  ['bad generation', file => writeFileSync(file, JSON.stringify({ ...JSON.parse(readFileSync(file)), generation: 'bad' }))],
+  ['loose mode', file => chmodSync(file, 0o644)],
+  ['oversized file', file => writeFileSync(file, ' '.repeat(8193))],
+]) test(`refuses ${name} instead of enabling work`, t => {
+  assert.equal(typeof api.initializeControl, 'function');
+  const dir = root(t); api.initializeControl(dir); edit(stateFile(dir));
+  assert.throws(() => api.assertProcessing(dir), refusal('processing-state-invalid'));
+});
+
+test('a symlink leaf never follows its target; human halt replaces only the leaf', t => {
+  assert.equal(typeof api.initializeControl, 'function');
+  const dir = root(t); api.initializeControl(dir);
+  const outside = join(dir, 'outside'), target = readFileSync(stateFile(dir));
+  writeFileSync(outside, target, { mode: 0o600 });
+  unlinkSync(stateFile(dir)); symlinkSync(outside, stateFile(dir));
+  assert.throws(() => api.readControl(dir), refusal('processing-state-invalid'));
+  api.transition(dir, { ...actor, halted: true });
+  assert.deepEqual(readFileSync(outside), target);
+  assert.equal(lstatSync(stateFile(dir)).isSymbolicLink(), false);
+});
+
+test('unsafe parent and interrupted initialization never get repaired as off', t => {
+  assert.equal(typeof api.initializeControl, 'function');
+  const dir = root(t); mkdirSync(join(dir, 'control'), { mode: 0o700 });
+  assert.throws(() => api.initializeControl(dir), refusal('processing-state-invalid'));
+  chmodSync(join(dir, 'control'), 0o777);
+  assert.throws(() => api.transition(dir, { ...actor, halted: true }), refusal('processing-control-unsafe'));
+});
+
+test('repeated halt is a no-op and a different root keeps running', t => {
+  assert.equal(typeof api.initializeControl, 'function');
+  const a = root(t), b = root(t); api.initializeControl(a); api.initializeControl(b);
+  const first = api.transition(a, { ...actor, halted: true });
+  const before = readFileSync(stateFile(a));
+  assert.equal(api.transition(a, { ...actor, halted: true }).generation, first.generation);
+  assert.deepEqual(readFileSync(stateFile(a)), before);
+  assert.doesNotThrow(() => api.assertProcessing(b));
+});
+
+// Coercing undefined/numbers through a regex would publish unverifiable actor metadata.
+test('transition rejects nonstring identity before publishing state', t => {
+  const dir = root(t); api.initializeControl(dir);
+  const before = readFileSync(stateFile(dir));
+  for (const bad of [undefined, null, 123, ['jason']]) {
+    assert.throws(() => api.transition(dir, { ...actor, human: bad, halted: true }), refusal('invalid-request'));
+    assert.deepEqual(readFileSync(stateFile(dir)), before);
+  }
+});
+
+// A lost control directory after power failure could permit a later off bootstrap.
+test('bootstrap syncs the containing root as well as the state and control directory', t => {
+  const dir = root(t);
+  const script = `import fs from 'node:fs'; import {syncBuiltinESMExports} from 'node:module';
+    const real=fs.fsyncSync, seen=[];
+    fs.fsyncSync=fd=>{seen.push(fs.readlinkSync('/proc/self/fd/'+fd));return real(fd)};
+    syncBuiltinESMExports();
+    const {initializeControl}=await import(process.argv[1]);initializeControl(process.argv[2]);
+    console.log(JSON.stringify(seen));`;
+  const result = spawnSync(process.execPath, ['--input-type=module', '-e', script,
+    new URL('../src/state.mjs', import.meta.url).href, dir], { encoding: 'utf8' });
+  assert.equal(result.status, 0, result.stderr);
+  const seen = JSON.parse(result.stdout);
+  assert.ok(seen.includes(dir), 'control mkdir must be durable in the root');
+  assert.ok(seen.includes(join(dir, 'control')), 'state rename must be durable');
+  assert.ok(seen.some(p => p.startsWith(join(dir, 'control', '.state-'))), 'state bytes must be durable');
+});
+
+// Each fstat/read guard is exercised independently, rather than hidden by a later parse refusal.
+test('state ownership and bounded read guards refuse before trusting a document', t => {
+  const dir = root(t); api.initializeControl(dir); const file = stateFile(dir);
+  const script = `import fs from 'node:fs';import {syncBuiltinESMExports} from 'node:module';
+    const stat=fs.fstatSync,read=fs.readSync;let reads=0;
+    const file=process.argv[2],which=process.argv[3],valid=fs.readFileSync(file);
+    if(which==='oversize')fs.writeFileSync(file,Buffer.concat([valid,Buffer.alloc(8193,32)]));
+    fs.fstatSync=fd=>{const s=stat(fd);if(fs.readlinkSync('/proc/self/fd/'+fd)===file){
+      if(which==='owner')s.uid++;
+      if(which==='grow')fs.writeFileSync(file,Buffer.concat([valid,Buffer.alloc(8193-valid.length,32)]));
+    }return s};
+    fs.readSync=(...args)=>{if(fs.readlinkSync('/proc/self/fd/'+args[0])===file)reads++;return read(...args)};syncBuiltinESMExports();
+    const {readControl}=await import(process.argv[1]);let code=null;
+    try{readControl(process.argv[4])}catch(e){code=e.code}console.log(JSON.stringify({code,reads}));`;
+  for (const which of ['owner', 'oversize', 'grow']) {
+    const valid = readFileSync(file);
+    const result = spawnSync(process.execPath, ['--input-type=module', '-e', script,
+      new URL('../src/state.mjs', import.meta.url).href, file, which, dir], { encoding: 'utf8' });
+    writeFileSync(file, valid);
+    assert.equal(result.status, 0, result.stderr);
+    const answer = JSON.parse(result.stdout); assert.equal(answer.code, 'processing-state-invalid', which);
+    if (which !== 'grow') assert.equal(answer.reads, 0, `${which}: refuse before reading bytes`);
+    else assert.ok(answer.reads > 0);
+  }
+});
+
+test('canonical root aliases address one switch and never create independent control state', t => {
+  const a = root(t), b = root(t), alias = join(b, 'alias');
+  api.initializeControl(a); symlinkSync(a, alias, 'dir');
+  assert.equal(api.initializeControl(alias).generation, api.readControl(a).generation);
+  const halted = api.transition(alias, { ...actor, halted: true });
+  assert.equal(api.readControl(a).generation, halted.generation);
+  assert.equal(api.readControl(a).halted, true);
+});

packages/processing-control/tests/stop-run.test.mjs

@@ -0,0 +1,183 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { mkdtempSync, rmSync, readFileSync } from 'node:fs';
+import { join } from 'node:path';
+import { tmpdir } from 'node:os';
+import { initializeControl, readControl, transition } from '../src/state.mjs';
+import { registerRuntime, updateRuntime, runtime, stopRun, sweepRuntimes, readStops } from '../src/runtimes.mjs';
+
+const boot = '12345678-1234-4234-8234-123456789abc';
+const decision = 'fire-decision';
+function setup(t, run = 'unbound-run') {
+  const root = mkdtempSync(join(tmpdir(), 'stop-run-')); initializeControl(root);
+  t.after(() => rmSync(root, { recursive: true, force: true }));
+  const r = registerRuntime(root, { kind: 'session', business: 'demo', run });
+  updateRuntime(root, r.id, { pid: 2000000001, startTime: '42', boot, phase: 'running', group: false });
+  let time = 0, live = true, changed = false;
+  const signals = [], sleeps = [];
+  const options = {
+    now: () => time,
+    sleep: async ms => { sleeps.push(ms); time += ms; },
+    identity: pid => live ? { pid, startTime: changed ? '43' : '42', boot } : null,
+    state: () => live,
+    signal: (_r, sig) => { signals.push(sig); if (sig === 'SIGKILL') live = false; return true; },
+  };
+  return { root, r, signals, sleeps, options,
+    setLive: value => { live = value; }, change: () => { changed = true; },
+    args: { root, business: 'demo', run, reason: 'fire', owner: { decision } } };
+}
+test('unbound run stops by verified registry identity, fixed 5s grace and 2s observe policy', async t => {
+  const f = setup(t), before = readControl(f.root);
+  const result = await stopRun(f.args, f.options);
+  assert.equal(result.outcome, 'killed'); assert.equal(result.pid, 2000000001);
+  assert.deepEqual(result.signals, ['SIGTERM', 'SIGKILL']);
+  assert.ok(f.sleeps.reduce((a,b)=>a+b,0) >= 5000);
+  assert.equal(result.receipt.reason, 'fire'); assert.deepEqual(result.receipt.owner, { decision });
+  assert.deepEqual(readControl(f.root), before, 'fire never halts the instance');
+});
+test('same run joins the identical promise and completed repeats preserve owner and send no signals', async t => {
+  const f = setup(t);
+  const first = stopRun(f.args, f.options), second = stopRun(f.args, f.options);
+  assert.equal(second, first);
+  const result = await first;
+  const later = await stopRun({ ...f.args, owner: { decision: 'other' } }, f.options);
+  assert.deepEqual(later, result); assert.deepEqual(f.signals, ['SIGTERM', 'SIGKILL']);
+});
+test('identity changed before TERM or between TERM and KILL refuses the changed signal', async t => {
+  for (const phase of ['before', 'after-term']) {
+    const f = setup(t, phase);
+    if (phase === 'before') f.change();
+    f.options.signal = (_r, sig) => { f.signals.push(sig); f.change(); return true; };
+    const result = await stopRun(f.args, f.options);
+    assert.equal(result.outcome, 'identity-changed');
+    assert.deepEqual(f.signals, phase === 'before' ? [] : ['SIGTERM']);
+    assert.deepEqual(result.signals, f.signals);
+  }
+});
+test('failed signal delivery observes alive, records no invented signals and never restarts escalation', async t => {
+  const f = setup(t); f.options.signal = () => false;
+  const result = await stopRun(f.args, f.options);
+  assert.equal(result.outcome, 'alive'); assert.deepEqual(result.signals, []);
+  assert.equal(f.sleeps.reduce((a,b)=>a+b,0), 7000);
+  assert.deepEqual(await stopRun(f.args, f.options), result);
+});
+test('missing run and another business never borrow a pid or signal', async t => {
+  const f = setup(t);
+  for (const args of [{ ...f.args, run: 'missing' }, { ...f.args, business: 'other' }]) {
+    const result = await stopRun(args, f.options);
+    assert.equal(result.outcome, 'unknown'); assert.equal(result.pid, null); assert.deepEqual(result.signals, []);
+  }
+  assert.deepEqual(f.signals, []);
+});
+test('halt joins an in-progress fire without another TERM or deadline and links its first receipt', async t => {
+  const f = setup(t); let entered, release;
+  const ready = new Promise(resolve => { entered = resolve; });
+  const gate = new Promise(resolve => { release = resolve; });
+  let blocked = false;
+  const sleep = f.options.sleep;
+  f.options.sleep = async ms => { if (!blocked) { blocked = true; entered(); await gate; } await sleep(ms); };
+  const first = stopRun(f.args, f.options); await ready;
+  const halted = transition(f.root, { business: 'demo', human: 'jason', halted: true });
+  const sweep = sweepRuntimes(f.root, halted.generation, { stopOptions: f.options });
+  release(); const result = await first, summary = await sweep;
+  assert.equal(summary.quiescent, true); assert.deepEqual(f.signals, ['SIGTERM', 'SIGKILL']);
+  const [link] = readStops(f.root, halted.generation);
+  assert.equal(link.stop, result.receipt.id); assert.equal(link.reason, 'fire');
+  assert.equal(runtime(f.root, f.r.id).haltGeneration, undefined, 'halt does not relabel a fire-owned stop');
+  assert.deepEqual(link.owner, { decision });
+});
+
+test('a separate host joins durable first ownership without duplicate signals', async t => {
+  const { spawn } = await import('node:child_process');
+  const { once } = await import('node:events');
+  const f = setup(t), source = new URL('../src/runtimes.mjs', import.meta.url).href;
+  const script = `import {stopRun} from ${JSON.stringify(source)};
+    let time=0,live=true,waiting=true;
+    const args=JSON.parse(process.argv[1]);
+    const result=await stopRun(args,{
+      now:()=>time, identity:pid=>live?{pid,startTime:'42',boot:${JSON.stringify(boot)}}:null,
+      state:()=>live,signal:(_r,sig)=>{process.send({signal:sig});if(sig==='SIGKILL')live=false;return true},
+      sleep:async ms=>{if(waiting){waiting=false;await new Promise(r=>process.once('message',r))}time+=ms}
+    });process.send({result});process.disconnect();`;
+  const child = spawn(process.execPath, ['--input-type=module', '-e', script, JSON.stringify(f.args)],
+    { detached: true, stdio: ['ignore', 'pipe', 'pipe', 'ipc'] });
+  t.after(() => { if (child.exitCode === null) { try { process.kill(-child.pid, 'SIGKILL'); } catch {} } });
+  const messages = []; child.on('message', value => messages.push(value));
+  await once(child, 'message');
+  const joined = stopRun({ ...f.args, owner: { decision: 'second-host' } },
+    { ...f.options, sleep: ms => new Promise(resolve => setTimeout(resolve, ms)) });
+  setTimeout(() => child.send('continue'), 30);
+  const result = await joined;
+  const exit = child.exitCode === null ? await once(child, 'exit') : [child.exitCode];
+  assert.equal(exit[0], 0);
+  assert.deepEqual(f.signals, [], 'the second host sends no signal');
+  assert.deepEqual(messages.filter(m => m.signal).map(m => m.signal), ['SIGTERM', 'SIGKILL']);
+  assert.equal(result.receipt.id, messages.find(m => m.result).result.receipt.id);
+  assert.deepEqual(result.receipt.owner, { decision });
+});
+
+test('corrupt and symlinked final receipts refuse as unknown rather than signalling again', async t => {
+  const { readdirSync, writeFileSync, symlinkSync, unlinkSync } = await import('node:fs');
+  const f = setup(t); const complete = await stopRun(f.args, f.options);
+  const dir = join(f.root, 'control', 'run-stops');
+  const name = readdirSync(dir).find(n => n.endsWith('.result.json'));
+  writeFileSync(join(dir, name), '{broken', { mode: 0o600 });
+  assert.equal((await stopRun(f.args, f.options)).outcome, 'unknown');
+  writeFileSync(join(dir, name), JSON.stringify({ ...complete.receipt, outcome: 'invented' }), { mode: 0o600 });
+  assert.equal((await stopRun(f.args, f.options)).outcome, 'unknown');
+  const target = join(f.root, 'outside'); writeFileSync(target, JSON.stringify(complete.receipt), { mode: 0o600 });
+  unlinkSync(join(dir, name)); symlinkSync(target, join(dir, name));
+  assert.equal((await stopRun(f.args, f.options)).outcome, 'unknown');
+  assert.deepEqual(f.signals, ['SIGTERM', 'SIGKILL']);
+});
+
+test('a later exit gets separate halt evidence while the original alive result stays immutable', async t => {
+  const { spawn } = await import('node:child_process');
+  const { once } = await import('node:events');
+  const { processIdentity } = await import('../src/runtimes.mjs');
+  const f = setup(t);
+  const child = spawn(process.execPath, ['-e', "console.log('ready');setInterval(()=>{},1000)"],
+    { detached: true, stdio: ['ignore', 'pipe', 'pipe'] });
+  t.after(() => { try { process.kill(-child.pid, 'SIGKILL'); } catch {} });
+  await once(child.stdout, 'data');
+  const identity = processIdentity(child.pid);
+  updateRuntime(f.root, f.r.id, { ...identity, group: false });
+  f.options.identity = () => identity; f.options.signal = () => false;
+  const first = await stopRun(f.args, f.options);
+  assert.equal(first.outcome, 'alive');
+  const bytes = JSON.stringify(first);
+  const ended = once(child, 'exit'); child.kill('SIGKILL'); await ended;
+  const state = transition(f.root, { business: 'demo', human: 'jason', halted: true });
+  assert.equal((await sweepRuntimes(f.root, state.generation)).quiescent, true);
+  assert.equal(JSON.stringify(await stopRun(f.args, f.options)), bytes);
+  const { readdirSync } = await import('node:fs');
+  assert.equal(readdirSync(join(f.root, 'control', 'run-stops')).filter(n => n.endsWith('.observation.json')).length, 1);
+});
+
+test('root aliases join but a different root never shares the run stop', async t => {
+  const { symlinkSync } = await import('node:fs');
+  const a = setup(t), b = setup(t);
+  const alias = a.root + '-alias'; symlinkSync(a.root, alias); t.after(() => rmSync(alias));
+  const first = stopRun(a.args, a.options);
+  assert.equal(stopRun({ ...a.args, root: alias }, a.options), first);
+  const other = stopRun(b.args, b.options);
+  assert.notEqual(other, first);
+  const [one, two] = await Promise.all([first, other]);
+  assert.notEqual(one.receipt.id, two.receipt.id);
+  assert.deepEqual(a.signals, ['SIGTERM', 'SIGKILL']); assert.deepEqual(b.signals, ['SIGTERM', 'SIGKILL']);
+});
+
+test('a changed runtime record cannot replace the original stop identity after TERM', async t => {
+  const f = setup(t);
+  f.options.signal = (_r, sig) => {
+    f.signals.push(sig); f.change(); updateRuntime(f.root, f.r.id, { startTime: '43' }); return true;
+  };
+  const result = await stopRun(f.args, f.options);
+  assert.equal(result.outcome, 'identity-changed'); assert.deepEqual(f.signals, ['SIGTERM']);
+});
+test('identity is rechecked at actual signal delivery, not just at the loop observation', async t => {
+  const f = setup(t); let reads = 0;
+  f.options.identity = pid => ({ pid, boot, startTime: ++reads === 1 ? '42' : '43' });
+  const result = await stopRun(f.args, f.options);
+  assert.equal(result.outcome, 'identity-changed'); assert.deepEqual(f.signals, []);
+});

packages/processing-control/tests/task.test.mjs

@@ -0,0 +1,68 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { spawnSync } from 'node:child_process';
+import { existsSync, mkdirSync, readFileSync, readdirSync, writeFileSync } from 'node:fs';
+import { join } from 'node:path';
+import { fixture, tmp } from '../../cli/tests/helpers.mjs';
+import { initializeControl, transition } from '../src/state.mjs';
+const TASK = new URL('../../../scripts/mosaic-task.mjs', import.meta.url).pathname;
+function setup(t, stop = false) {
+  const root = tmp(t), f = fixture(root), bin = join(root, 'bin'); mkdirSync(bin);
+  const source = new URL('../src/state.mjs', import.meta.url).href;
+  const runtimes = new URL('../src/runtimes.mjs', import.meta.url).href;
+  writeFileSync(join(bin, 'docker'), `#!${process.execPath}
+(async()=>{const args=process.argv.slice(2);require('node:fs').writeFileSync(${JSON.stringify(join(root, 'called'))},JSON.stringify(args));
+${stop ? `const {transition}=await import(${JSON.stringify(source)});const {updateRuntime}=await import(${JSON.stringify(runtimes)});const s=transition(process.env.MOSAIC_DATA_ROOT,{business:'acme',human:'jason',halted:true});const tag=args.find(x=>x.startsWith('mosaic.runtime='));if(tag)updateRuntime(process.env.MOSAIC_DATA_ROOT,tag.slice(15),{haltGeneration:s.generation});process.exit(137);` : `console.log('normal response');`}
+})().catch(e=>{console.error(e.message);process.exit(1)});\n`, { mode: 0o755 });
+  f.env.PATH = bin + ':' + f.env.PATH;
+  const task = join(root, 'task.json'); writeFileSync(task, JSON.stringify({ taskVersion: 1, id: 'one', prompt: 'request' }));
+  const run = args => spawnSync(process.execPath, [TASK, ...args], { env: f.env, encoding: 'utf8', timeout: 10000 });
+  return { root, f, task, run };
+}
+test('task halt keeps the true Docker exit status, writes kill-switch once and leaves snapshots unchanged', t => {
+  const f = setup(t, true), result = f.run(['run', f.task]);
+  assert.equal(result.status, 1, result.stderr);
+  const runs = join(f.f.dataRoot, 'runs'), [id] = readdirSync(runs);
+  const file = join(runs, id, 'result.json'), bytes = readFileSync(file), record = JSON.parse(bytes);
+  assert.equal(record.reason, 'kill-switch'); assert.match(record.haltGeneration, /^[a-f0-9-]{36}$/);
+  assert.equal(record.exitCode, 137); assert.equal(record.signal, null);
+  assert.deepEqual(readFileSync(join(runs, id, 'task.json')), readFileSync(f.task));
+  const retry = f.run(['retry', id]); assert.equal(retry.status, 3, retry.stderr);
+  assert.deepEqual(readFileSync(file), bytes); assert.deepEqual(readdirSync(runs), [id]);
+});
+test('halt refuses direct task launch before Docker or a run record; clear allows a fresh normal result', t => {
+  const f = setup(t), actor = { business: 'acme', human: 'jason' };
+  initializeControl(f.f.dataRoot); const halted = transition(f.f.dataRoot, { ...actor, halted: true });
+  const result = f.run(['run', f.task]); assert.equal(result.status, 3, result.stderr);
+  assert.equal(existsSync(join(f.root, 'called')), false);
+  assert.equal(existsSync(join(f.f.dataRoot, 'runs')), false);
+  transition(f.f.dataRoot, { ...actor, halted: false, generation: halted.generation });
+  const normal = f.run(['run', f.task]); assert.equal(normal.status, 0, normal.stderr);
+  const [id] = readdirSync(join(f.f.dataRoot, 'runs'));
+  const record = JSON.parse(readFileSync(join(f.f.dataRoot, 'runs', id, 'result.json')));
+  assert.equal(record.reason, null); assert.equal(record.status, 'succeeded');
+  assert.equal(record.response, 'normal response'); assert.equal('haltGeneration' in record, false);
+});
+
+for (const [script, args] of [['hello.sh', []], ['verify.sh', []], ['agent.sh', ['fixture']]]) {
+  test(`halt refuses ${script} before Docker, credentials or release alignment`, t => {
+    const f = setup(t); initializeControl(f.f.dataRoot);
+    transition(f.f.dataRoot, { business: 'acme', human: 'jason', halted: true });
+    const r = spawnSync('bash', [new URL('../../../scripts/' + script, import.meta.url).pathname, ...args],
+      { env: f.f.env, encoding: 'utf8', timeout: 5000 });
+    assert.equal(r.status, 3, r.stderr); assert.match(r.stderr, /processing-halted/);
+    assert.equal(existsSync(join(f.root, 'called')), false);
+  });
+}
+
+for (const starter of ['task', 'container-cli']) test(`a nonzero Docker client exit retains its unresolved runtime receipt (${starter})`, t => {
+  const f = setup(t);
+  writeFileSync(join(f.root, 'bin', 'docker'), `#!${process.execPath}\nprocess.exit(137);\n`, { mode: 0o755 });
+  const result = starter === 'task' ? f.run(['run', f.task]) : spawnSync(process.execPath,
+    [new URL('../src/container-cli.mjs', import.meta.url).pathname, 'request'], { env: f.f.env, encoding: 'utf8', timeout: 10000 });
+  assert.equal(result.status, starter === 'task' ? 1 : 137, result.stderr);
+  const files = readdirSync(join(f.f.dataRoot, 'control', 'runtimes'));
+  assert.equal(files.length, 1, 'a failed Docker client cannot prove the container stopped');
+  const runtime = JSON.parse(readFileSync(join(f.f.dataRoot, 'control', 'runtimes', files[0])));
+  assert.notEqual(runtime.phase, 'ended');
+});

packages/project/src/git.mjs

@@ -3,6 +3,7 @@ import { dirname, join } from 'node:path';
 import { spawn } from 'node:child_process';
 import { gitEnv, runGit, GIT_LIMITS } from '../../seat/src/checkout.mjs';
 import { ProjectError } from './paths.mjs';
+import { currentProcessing } from '../../processing-control/src/effects.mjs';
 
 export const SAFE = ['-c', 'core.hooksPath=/dev/null', '-c', 'core.fsmonitor=false', '-c', 'core.ignorestat=false',
   '-c', 'protocol.allow=never', '-c', 'submodule.recurse=false', '-c', 'commit.gpgsign=false',
@@ -58,10 +59,13 @@ export const identity = name => ({ GIT_AUTHOR_NAME: name, GIT_AUTHOR_EMAIL: `${n
 // Blob/log reads preserve bytes and bound memory before decoding untrusted Git data.
 export async function gitBytes(repo, args, maxBytes) {
   return new Promise((resolve, reject) => {
+    const processing = currentProcessing();
+    processing?.guard();
     const child = spawn('git', [...SAFE, '-C', repo, ...args], {
       env: { ...gitEnv(), GIT_CEILING_DIRECTORIES: dirname(repo) },
       detached: true, stdio: ['ignore', 'pipe', 'pipe'],
     });
+    processing?.track(child);
     let size = 0, failed = false, settled = false;
     const chunks = [];
     const kill = () => { try { process.kill(-child.pid, 'SIGKILL'); } catch {} };

packages/seat/src/checkout.mjs

@@ -45,6 +45,7 @@ import { spawn } from "node:child_process";
 import { randomBytes } from "node:crypto";
 import { closeSync, lstatSync, openSync, readdirSync, renameSync, rmSync } from "node:fs";
 import { dirname, join } from "node:path";
+import { currentProcessing } from '../../processing-control/src/effects.mjs';
 
 export const GIT_TIMEOUT_MS = 100_000;
 // How long a git has after SIGTERM before SIGKILL.
@@ -106,6 +107,8 @@ export function gitEnv(env = process.env) {
 // reads its token there, so the token is in no argv, env, URL or file.
 export function runGit(argv, env, limits = GIT_LIMITS, { stdin = null, pass = null } = {}) {
   return new Promise((resolve) => {
+    const processing = currentProcessing();
+    processing?.guard();
     let input = "ignore";
     try {
       if (stdin !== null) input = openSync(stdin, "r");
@@ -113,6 +116,7 @@ export function runGit(argv, env, limits = GIT_LIMITS, { stdin = null, pass = nu
       return resolve({ ok: false, out: "", err: "", why: e.code ?? e.message });
     }
     const child = spawn("git", argv, { env, detached: true, stdio: [input, "pipe", "pipe", ...(pass === null ? [] : ["pipe"])] });
+    processing?.track(child);
     if (typeof input === "number") closeSync(input);
     // A git that never asked for it closes the pipe unread: EPIPE is no fault.
     if (pass !== null) child.stdio[3].on("error", () => {}).end(pass);

packages/seat/src/landing.mjs

@@ -19,6 +19,7 @@ import { appendFileSync, existsSync, lstatSync, openSync, closeSync, readdirSync
 import { join } from "node:path";
 import { pathToFileURL } from "node:url";
 import { gitEnv, runGit } from "./checkout.mjs";
+import { currentProcessing } from '../../processing-control/src/effects.mjs';
 
 // The new foundation's root commit, "chore: baseline container POC and atomic
 // foundation plan" (2026-09-02, tag poc-container-hello-v0). A project whose
@@ -119,6 +120,7 @@ export async function runGate({ worktree, logs, env = process.env, signal = null
 // The step's exit code, or null when the signal stopped it.
 function runStep(step, worktree, log, env, signal) {
   return new Promise((resolve) => {
+    const processing = currentProcessing(); processing?.guard();
     const fd = openSync(log, "w");
     const child = spawn("bash", ["-c", `set -o pipefail; ${step.command}`], {
       cwd: join(worktree, step.dir),
@@ -126,6 +128,7 @@ function runStep(step, worktree, log, env, signal) {
       detached: true,
       stdio: ["ignore", fd, fd],
     });
+    processing?.track(child);
     closeSync(fd);
     let kill = null;
     const group = (sig) => {

packages/seat/src/sandbox.mjs

@@ -60,6 +60,7 @@ export const RUNNER_FILES = Object.freeze([
   "packages/bus/src/landing.mjs",
   "packages/business/src/vocabulary.mjs",
   "packages/plugins/src/kinds.mjs",
+  "packages/processing-control/src/state.mjs",
   "packages/tasks/src/requirements.mjs",
 ].map((p) => join(REPO, p)));
 

packages/seat/src/working.mjs

@@ -84,6 +84,7 @@ import { randomBytes } from "node:crypto";
 import { closeSync, lstatSync, mkdirSync, openSync, readSync, renameSync, rmSync, writeFileSync } from "node:fs";
 import { dirname, join } from "node:path";
 import { gitEnv, GIT_LIMITS, runGit } from "./checkout.mjs";
+import { withoutProcessing } from '../../processing-control/src/effects.mjs';
 
 // The largest bundle the host takes or sends.
 export const BUNDLE_MAX = 32 * 1024 * 1024;
@@ -247,7 +248,7 @@ export function push({ dataRoot, business, project, root, taskRef, branch, bundl
         await record({ ref: workRef(taskRef), commit, previous });
       } catch (e) {
         const back = previous ? ["update-ref", ref, previous, commit] : ["update-ref", "-d", ref, commit];
-        const undone = await g([...at, ...back]);
+        const undone = await withoutProcessing(() => g([...at, ...back]));
         // The ref still names a commit the broker didn't record. That is the
         // operator's to fix, so it outranks record's own error.
         if (!undone.ok) refuse("rollback-failed", `${ref} still names ${commit}, which wasn't recorded (${e.code ?? e.message}); moving it back failed: ${undone.why}`);
@@ -255,7 +256,7 @@ export function push({ dataRoot, business, project, root, taskRef, branch, bundl
       }
       return { ref: workRef(taskRef), commit, previous };
     } finally {
-      await g([...at, "update-ref", "-d", incoming]);
+      await withoutProcessing(() => g([...at, "update-ref", "-d", incoming]));
     }
   });
 }
@@ -287,7 +288,7 @@ export function review({ dataRoot, business, project, root, taskRef, commit, hav
       const made = await g([...at, "bundle", "create", "-q", out, temp, ...(known.length ? ["--not", ...known] : [])]);
       if (!made.ok) refuse(/empty bundle/.test(made.err) ? "nothing-to-fetch" : "fetch-failed", made.why);
     } finally {
-      await g([...at, "update-ref", "-d", temp]);
+      await withoutProcessing(() => g([...at, "update-ref", "-d", temp]));
     }
     return { ref: workRef(taskRef), commit };
   });
@@ -373,7 +374,7 @@ export function prepareLand({ dataRoot, business, project, root, taskRef, commit
       if (!(await g([...wt, "reset", "-q", "--soft", squash])).ok) refuse("git-failed", "the worktree couldn't move to the squash");
       return { worktree, old, commit: squash, base, reviewed: commit, patch_id };
     } catch (e) {
-      await removeWorktree(repo, worktree, g);
+      await withoutProcessing(() => removeWorktree(repo, worktree, g));
       throw e;
     }
   });
@@ -393,7 +394,7 @@ export function finishLand({ dataRoot, business, project, land, record = async (
     try {
       await record({ previous: land.old, commit: land.commit });
     } catch (e) {
-      const undone = await g([...at, "update-ref", main, land.old, land.commit]);
+      const undone = await withoutProcessing(() => g([...at, "update-ref", main, land.old, land.commit]));
       if (!undone.ok) refuse("rollback-failed", `main still names ${land.commit}, which wasn't recorded (${e.code ?? e.message}); moving it back to ${land.old} failed: ${undone.why}`);
       throw e;
     }
@@ -406,7 +407,7 @@ export function finishLand({ dataRoot, business, project, land, record = async (
 // node_modules link the gate added goes first, so nothing follows it.
 export function dropLand({ dataRoot, business, project, worktree, env = process.env, limits = GIT_LIMITS }) {
   const repo = workingRepo(dataRoot, business, project);
-  return locked(repo, () => removeWorktree(repo, worktree, bound(env, limits)));
+  return withoutProcessing(() => locked(repo, () => removeWorktree(repo, worktree, bound(env, limits))));
 }
 
 async function removeWorktree(repo, worktree, g) {

packages/seat/tests/working.test.mjs

@@ -579,3 +579,16 @@ test("finish refuses base-moved when main moved, and a record that throws moves
   assert.deepEqual(locks(w.repo), []);
   assert.deepEqual(trees(w), []);
 });
+
+// Row 191: a halt at receipt time must not prevent the existing compare-and-swap rollback.
+test('halted push receipt rolls back only its unrecorded ref and cleans temporary refs', async t => {
+  const { initializeControl, transition } = await import('../../processing-control/src/state.mjs');
+  const { withProcessing } = await import('../../processing-control/src/effects.mjs');
+  const w = world(t); initializeControl(w.dataRoot);
+  git(w.clone, 'checkout', '-q', '-b', 'feat'); commit(w.clone, 'two');
+  await assert.rejects(withProcessing(w.dataRoot, () => w.go(w.bundle(), { record: async () => {
+    transition(w.dataRoot, { business: 'acme', human: 'jason', halted: true });
+    throw Error('not recorded after halt');
+  } })), /not recorded after halt/);
+  assert.equal(w.refs(), `refs/heads/main ${w.first}\nrefs/heads/root ${w.first}`);
+});

packages/tasks/src/adapter.mjs

@@ -10,7 +10,7 @@ import { verbs } from './verbs.mjs';
 // without waiting on Vikunja; verbs refuse with tracker-starting until it passes.
 export const TIMEOUT = 60000;
 // Refusals that a later startup attempt can clear. A scope or install refusal waits for a restart.
-const TRANSIENT = new Set(['tracker-unavailable', 'tracker-rate-limited', 'service-failed']);
+const TRANSIENT = new Set(['tracker-unavailable', 'tracker-rate-limited', 'service-failed', 'processing-halted', 'processing-generation-changed']);
 const code = (e) => (e instanceof BusError ? e.code : 'adapter-failed');
 const positive = (x) => Number.isSafeInteger(x) && x > 0;
 function settings(name, t, b) {
@@ -61,7 +61,7 @@ export function tasksAdapter({
   log = (line) => process.stderr.write(line + '\n'),
   autostart = true,
 } = {}) {
-  return async function factory({ broker, credentials, businesses }) {
+  return async function factory({ broker, credentials, businesses, processing = null }) {
     const contexts = new Map();
     for (const [name, t] of Object.entries(trackers)) {
       const s = settings(name, t, businesses[name]);
@@ -107,7 +107,13 @@ export function tasksAdapter({
     let closed = false;
     // One operation at a time per business: a tick never reads mid-write.
     const serial = (ctx, fn) => {
-      const run = ctx.queue.then(() => (closed ? Promise.reject(new BusError('tracker-closed')) : fn()));
+      const run = ctx.queue.then(() => {
+        if (closed) throw new BusError('tracker-closed');
+        return processing ? processing.work(fn).catch(e => {
+          if (e.name === 'ProcessingError') throw new BusError(e.code);
+          throw e;
+        }) : fn();
+      });
       ctx.queue = run.catch(() => {});
       return run;
     };
@@ -116,6 +122,10 @@ export function tasksAdapter({
       ctx.pending++;
       return serial(ctx, fn)
         .catch((e) => {
+          if (e.code?.startsWith('processing-')) {
+            ctx.state = 'refused';
+            ctx.refused = e.code;
+          }
           if (!closed) log(`tasks ${ctx.business} ${what} ${code(e)}`);
         })
         .finally(() => ctx.pending--);

packages/tasks/src/vikunja.mjs

@@ -1,4 +1,5 @@
 import { BusError } from '../../bus/src/broker.mjs';
+import { currentProcessing } from '../../processing-control/src/effects.mjs';
 // Vikunja v2 HTTP client. It never throws: a network error or timeout is status 0, so
 // credentials.use() gets a result back instead of flattening a throw to service-failed.
 // The token goes only into the Authorization header; nothing here logs.
@@ -29,6 +30,8 @@ const query = (q) =>
 export function client({ baseUrl, fetch = globalThis.fetch, timeoutMs = 15000 }) {
   const root = apiRoot(baseUrl);
   return async function call(token, method, path, { body, query: q, etag } = {}) {
+    const processing = currentProcessing();
+    processing?.guard();
     const qs = query(q);
     const headers = { Accept: 'application/json' };
     if (token) headers.Authorization = `Bearer ${token}`;
@@ -40,7 +43,7 @@ export function client({ baseUrl, fetch = globalThis.fetch, timeoutMs = 15000 })
         headers,
         body: body === undefined ? undefined : JSON.stringify(body),
         redirect: 'error',
-        signal: AbortSignal.timeout(timeoutMs),
+        signal: processing ? AbortSignal.any([processing.signal, AbortSignal.timeout(timeoutMs)]) : AbortSignal.timeout(timeoutMs),
       });
       const text = await r.text();
       let json = null;

packages/tasks/tests/processing.test.mjs

@@ -0,0 +1,53 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { world } from './world.mjs';
+import { tasksAdapter } from '../src/adapter.mjs';
+import { createProcessing } from '../../processing-control/src/coordinator.mjs';
+import { transition } from '../../processing-control/src/state.mjs';
+const actor = { business: 'demo', human: 'jason', halted: true };
+test('halted tracker startup makes no fetch and a later clear permits its ordinary startup', async t => {
+  const w = await world(t), processing = createProcessing({ dataRoot: w.root });
+  let calls = 0;
+  const adapter = await tasksAdapter({ trackers: { demo: { baseUrl: 'http://vikunja.test', project: w.project } },
+    autostart: false, fetch: (...args) => { calls++; return w.fake.fetch(...args); }, log: () => {} })
+    ({ broker: w.broker, credentials: w.credentials, businesses: w.businesses, processing });
+  t.after(async () => { await adapter.close(); await processing.close(); });
+  const halted = transition(w.root, actor);
+  await assert.rejects(adapter.start('demo'), e => e.code === 'processing-halted');
+  assert.equal(calls, 0);
+  transition(w.root, { ...actor, halted: false, generation: halted.generation });
+  await adapter.start('demo'); assert.ok(calls > 0); assert.equal(adapter.status()[0].state, 'ready');
+  transition(w.root, actor); calls = 0;
+  await assert.rejects(adapter.tick('demo'), e => e.code === 'processing-halted');
+  await assert.rejects(adapter.reconcile('demo'), e => e.code === 'processing-halted');
+  assert.equal(calls, 0);
+});
+test('halt aborts the tracker HTTP request already in progress', async t => {
+  const w = await world(t), processing = createProcessing({ dataRoot: w.root });
+  let ready, aborted = false;
+  const started = new Promise(resolve => { ready = resolve; });
+  const adapter = await tasksAdapter({ trackers: { demo: { baseUrl: 'http://vikunja.test', project: w.project } },
+    autostart: false, log: () => {}, fetch: (_url, init) => new Promise((_resolve, reject) => {
+      init.signal.addEventListener('abort', () => { aborted = true; reject(Error('fixture abort')); }, { once: true }); ready();
+    }) })({ broker: w.broker, credentials: w.credentials, businesses: w.businesses, processing });
+  t.after(async () => { await adapter.close(); await processing.close(); });
+  const run = adapter.start('demo'); await started; const began = Date.now(); transition(w.root, actor);
+  await run.catch(() => {}); assert.equal(aborted, true);
+  assert.ok(Date.now() - began < 2000, 'halt must abort before the ordinary 15-second HTTP deadline');
+});
+
+test('an initially halted background startup remains retryable after clear', async t => {
+  const w = await world(t), processing = createProcessing({ dataRoot: w.root }), ticks = [];
+  const halted = transition(w.root, actor); let calls = 0;
+  const adapter = await tasksAdapter({ trackers: { demo: { baseUrl: 'http://vikunja.test', project: w.project } },
+    log: () => {}, timers: { setInterval: fn => { ticks.push(fn); return { unref() {} }; }, clearInterval() {} },
+    fetch: (...args) => { calls++; return w.fake.fetch(...args); } })
+    ({ broker: w.broker, credentials: w.credentials, businesses: w.businesses, processing });
+  t.after(async () => { await adapter.close(); await processing.close(); });
+  await adapter.ready; assert.equal(calls, 0); assert.equal(adapter.status()[0].refused, 'processing-halted');
+  transition(w.root, { ...actor, halted: false, generation: halted.generation });
+  ticks[0]();
+  for (let i = 0; i < 100 && adapter.status()[0].state !== 'ready'; i++)
+    await new Promise(resolve => setTimeout(resolve, 10));
+  assert.equal(adapter.status()[0].state, 'ready'); assert.ok(calls > 0);
+});

packages/webui/README.md

@@ -1053,3 +1053,17 @@ or unit flags are installed by this code change. Activation is a separately
 plan-checked Mos window: proxy middleware first, then Console flags and restart;
 rollback removes flags before middleware. Do not reuse console-allowed-uid,
 which is an identity rather than a proxy secret.
+
+## Instance processing controls
+
+The persistent Stop processing control and halted banner sit outside the
+route-specific views. GET /api/processing remains read-only. POST
+/api/processing/halt and /api/processing/resume use the existing human writer,
+`--send`, named same-origin checks and bounded strict JSON; a tester cannot
+write them. Resume asks for confirmation and submits the displayed generation.
+Unknown outcomes stay explicit and no write is retried.
+
+During Q175's read-only interim both buttons show as unavailable and point to
+`mosaic halt` / `mosaic resume` in the instance CLI. There is no halt-only send
+exception or alternate authentication path. Landing the UI and activating it
+remain separately gated.

packages/webui/src/cli.mjs

@@ -65,10 +65,12 @@ try {
   // no notifier. A refusal printed here names no path (redactor).
   // --send without a bus refuses to start rather than serve a composer that can't send.
   let bus = null, send = null, settingsWrite = null, projectFiles = null, projectFile = null, libraryFile = null, libraryStatus = null, librarySync = null, projectSave = null, chat = null, nameWrite = null, assistantStop = null, instancesWrite = null, routesWrite = null, busLine, system = null;
+  let processing = null;
   try {
     system = loadSystem();
     const { dataRoot } = system;
     const call = busCaller({ dataRoot, socket: socketPath(dataRoot), business: options.business ?? null });
+    processing = { read: () => call('processing.status'), halt: args => call('processing.halt', args), resume: args => call('processing.resume', args) };
     chat = createChat({ call });
     // Row 155 (#1649): `names` is a webui read only, so it sits beside the shared views. Row 165
     // (#1662): so is `instances`, and its write `instances.set` is only under --send. Row 65
@@ -98,7 +100,7 @@ try {
   }
   let server;
   try {
-    server = await startServer({ board: options.board, port: options.port, bus, reads, preview: options.preview, sso, proof, send, settingsWrite, projectFiles, projectFile, libraryFile, libraryStatus, librarySync, projectSave, chat, nameWrite, assistantStop, instancesWrite, routesWrite });
+    server = await startServer({ board: options.board, port: options.port, bus, reads, preview: options.preview, sso, proof, send, settingsWrite, projectFiles, projectFile, libraryFile, libraryStatus, librarySync, projectSave, chat, nameWrite, assistantStop, instancesWrite, routesWrite, processing });
   } catch (err) { sso?.close(); throw err; }
   let testerServer = null;
   if (testerSocket) {
@@ -107,6 +109,7 @@ try {
     try {
       testerServer = await startTesterSocket({ dataRoot: system.dataRoot, board: options.board,
         tester: true, testerNoSignIn: ssoOn, testerProofHeader: proof?.header ?? null, testerAuthHeader: options.preview?.header ?? null, bus: testerBus, reads,
+        processing: { read: () => call('processing.status') },
         projectFiles: args => call('project.files', args), projectFile: args => call('project.file', args),
         libraryFile: args => call('library.file', args), libraryStatus: args => call('library.status', args),
         instancesWrite: args => call('instances.set', args), routesWrite: args => call('routes.set', args), nameWrite: args => call('name.set', args),

packages/webui/src/processing-http.mjs

@@ -0,0 +1,50 @@
+// Instance control uses the existing management transport, independently of channels.
+const UUID = /^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/;
+const one = (req, key) => req.headersDistinct[key]?.length === 1 ? req.headersDistinct[key][0] : null;
+const json = (res, status, value) => { res.writeHead(status, { 'content-type': 'application/json', 'cache-control': 'no-store' }); res.end(JSON.stringify(value)); };
+const errors = { 'human-required': 403, 'read-only': 403, 'processing-state-invalid': 409,
+  'processing-control-unsafe': 409, 'processing-uninitialized': 409, 'processing-stop-pending': 409,
+  'processing-generation-changed': 409, 'not-configured': 503, 'outcome-unknown': 503 };
+function answer(value) {
+  if (!value || typeof value !== 'object' || Array.isArray(value) ||
+      ![true, false, null].includes(value.halted) || (value.invalid !== true &&
+      (value.version !== 1 || typeof value.generation !== 'string' || !UUID.test(value.generation))) ||
+      (value.quiescent !== undefined && typeof value.quiescent !== 'boolean')) throw Error('invalid receipt');
+  return Object.fromEntries(['version', 'generation', 'halted', 'invalid', 'code', 'at', 'quiescent', 'remaining',
+    'stopped', 'stopping', 'recovered'].filter(k => Object.hasOwn(value, k)).map(k => [k, value[k]]));
+}
+export async function processingHTTP(req, res, { path, search, processing, named, send, preview }) {
+  const write = req.method === 'POST';
+  const refuse = (status, code, sent = false) => json(res, status, { error: code,
+    message: code === 'outcome-unknown' ? 'Outcome unknown. Read processing status. Nothing was retried.' : 'Processing control refused.',
+    ...(write ? { sent } : {}) });
+  if (req.method !== 'GET' && !write) return refuse(405, 'method-not-allowed');
+  if (search) return refuse(400, 'invalid-request');
+  if (!write && path !== '/api/processing') return refuse(405, 'method-not-allowed');
+  let action = 'read', args = {};
+  if (write) {
+    if (!send || !named || !preview) return refuse(403, 'read-only');
+    if (preview.sso !== true && one(req, preview.header) !== preview.user) return refuse(401, 'unauthenticated');
+    if (one(req, 'origin') !== (preview.origin ?? `https://${preview.host}`)) return refuse(403, 'cross-origin');
+    if (one(req, 'sec-fetch-site') !== 'same-origin') return refuse(403, 'cross-site');
+    if (one(req, 'content-type')?.split(';')[0].trim().toLowerCase() !== 'application/json') return refuse(415, 'invalid-request');
+    if (!['/api/processing/halt', '/api/processing/resume'].includes(path)) return refuse(404, 'not-found');
+    action = path.endsWith('/halt') ? 'halt' : 'resume';
+    try {
+      let size = 0; const chunks = [];
+      for await (const chunk of req) { size += chunk.length; if (size > 1024) throw Error(); chunks.push(chunk); }
+      args = JSON.parse(Buffer.concat(chunks).toString('utf8'));
+      if (!args || typeof args !== 'object' || Array.isArray(args)) throw Error();
+      if (action === 'halt' ? Object.keys(args).length !== 0 :
+          Object.keys(args).length !== 1 || typeof args.generation !== 'string' || !UUID.test(args.generation)) throw Error();
+    } catch { return refuse(400, 'invalid-request'); }
+  }
+  if (typeof processing?.[action] !== 'function') return refuse(503, 'not-configured');
+  try {
+    const value = answer(await processing[action](args));
+    return json(res, write && value.quiescent === false ? 202 : 200, value);
+  } catch (e) {
+    const code = Object.hasOwn(errors, e.code) ? e.code : 'outcome-unknown';
+    return refuse(errors[code], code, code === 'outcome-unknown' ? 'unknown' : false);
+  }
+}

packages/webui/src/public/index.html

@@ -3,6 +3,7 @@
 <head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1"><title>Mosaic Console</title>
 <link rel="stylesheet" href="/shared/app.css"><link rel="stylesheet" href="/tokens.css"><link rel="stylesheet" href="/console.css"><link rel="stylesheet" href="/live.css"><link rel="stylesheet" href="/bus.css"><link rel="stylesheet" href="/chat.css"><link rel="stylesheet" href="/shell.css">
 <link rel="stylesheet" href="/editor.css"><script src="/editor.js" defer></script>
+<link rel="stylesheet" href="/processing.css"><script src="/processing.js" defer></script>
 <script src="/brand.js" defer></script><script src="/app.js" defer></script><script src="/markdown-preview.js" defer></script><script src="/chat.js" defer></script><script src="/bus.js" defer></script></head>
 <body>
 <a class="skip" href="#main">Skip to content</a>
@@ -10,6 +11,13 @@
 <button type="button" class="cmdk" id="cmdk" aria-haspopup="dialog" aria-controls="cmdk-dialog"><svg class="i" aria-hidden="true"><use href="/icons.svg#i-search"/></svg><span>Go to a view, decision or task</span><kbd>Ctrl K</kbd></button>
 <p class="fresh" id="fresh"><span id="fresh-board"></span><span id="fresh-bus"></span></p>
 <div class="cmd-right"><label>Palette<select id="palette"></select></label><label>Appearance<select id="mode"><option value="system">system</option><option value="light">light</option><option value="dim">dim</option><option value="dark">dark</option></select></label><button class="btn" id="refresh" type="button">Refresh</button><button class="btn" id="pause" type="button" aria-pressed="false">Pause</button><form id="sign-out" method="post" action="/auth/logout" hidden><button class="btn" type="submit">Sign out</button></form></div></header>
+<div id="processing-controls" class="processing-controls" role="region" aria-label="Instance processing">
+<strong>Processing</strong><p id="processing-state" role="status">Reading processing state.</p>
+<button id="processing-halt" type="button" class="btn" disabled>Stop processing</button>
+<button id="processing-resume" type="button" class="btn" disabled hidden>Resume processing</button>
+<p id="processing-unavailable" class="processing-note small muted">Processing controls are unavailable here. Use mosaic halt or mosaic resume from the instance CLI.</p>
+<p id="processing-receipt" class="processing-receipt small" aria-live="polite"></p></div>
+<div id="processing-banner" class="processing-banner" role="alert" hidden></div>
 <div class="frame">
 <nav class="tree" aria-label="Console"><h2 class="tree-title">Console</h2><ul class="s1-sections" id="sections"></ul><div id="board-tree"><h2 class="tree-title">Projects</h2><div id="projects"><p class="muted">Loading projects…</p></div><p class="small muted">Select a project to filter sessions. Waiting on you always shows all projects.</p></div></nav>
 <main id="main" class="content" tabindex="-1"><div id="signed-out" class="banner ref" role="alert" tabindex="-1" hidden></div><div id="bus-down" class="banner err" role="alert" hidden></div><div class="page-head" id="board-head"><div><h1>Control board</h1><p id="status" class="small muted" role="status">Loading board…</p></div><div class="filters"><label><input id="show-machine" type="checkbox">Show machine sessions</label></div></div>

packages/webui/src/public/processing.css

@@ -0,0 +1,7 @@
+.processing-controls { display:flex; flex-wrap:wrap; gap:.6rem; align-items:center; padding:.7rem 1rem; border-bottom:1px solid var(--line); }
+.processing-controls p { margin:0; }
+.processing-controls .processing-note, .processing-controls .processing-receipt { flex-basis:100%; }
+.processing-controls[data-state="halted"] { border-left:4px solid currentColor; }
+.processing-controls button:focus-visible { outline:3px solid currentColor; outline-offset:3px; }
+.processing-banner { padding:.75rem 1rem; font-weight:600; border-bottom:2px solid currentColor; }
+.processing-controls [hidden], .processing-banner[hidden] { display:none; }

packages/webui/src/public/processing.js

@@ -0,0 +1,68 @@
+/* Durable instance controls, outside all route-specific views. */
+(() => {
+  const byId = id => document.getElementById(id);
+  const host = byId('processing-controls');
+  if (!host) return;
+  const status = byId('processing-state'), halt = byId('processing-halt'), resume = byId('processing-resume');
+  const unavailable = byId('processing-unavailable'), receipt = byId('processing-receipt'), banner = byId('processing-banner');
+  const UUID = /^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/;
+  let snapshot = null, canWrite = false, busy = false, sequence = 0;
+  function draw() {
+    const halted = snapshot?.halted === true, valid = snapshot?.version === 1 && UUID.test(snapshot?.generation);
+    host.dataset.state = halted ? 'halted' : snapshot?.halted === false ? 'running' : 'unknown';
+    status.textContent = halted ? snapshot.stopping ? 'Processing halted. Stopping workloads.' : 'Processing halted.'
+      : snapshot?.halted === false ? 'Processing is enabled.' : 'Processing state unavailable.';
+    banner.hidden = !halted;
+    banner.textContent = 'Processing is halted for this instance. Reads and human recovery controls remain available.';
+    halt.disabled = !canWrite || busy;
+    resume.hidden = !halted;
+    resume.disabled = !canWrite || busy || !valid;
+    unavailable.hidden = canWrite;
+    unavailable.textContent = 'Processing controls are unavailable here. Use mosaic halt or mosaic resume from the instance CLI.';
+  }
+  async function refresh() {
+    if (busy) return;
+    const current = ++sequence;
+    try {
+      const [configResponse, stateResponse] = await Promise.all([
+        fetch('/api/config', { cache: 'no-store' }), fetch('/api/processing', { cache: 'no-store' }),
+      ]);
+      const [config, state] = await Promise.all([configResponse.json(), stateResponse.json()]);
+      if (current !== sequence) return;
+      canWrite = configResponse.ok && config.send === true;
+      snapshot = stateResponse.ok && [true, false, null].includes(state.halted) ? state : null;
+    } catch {
+      if (current !== sequence) return;
+      canWrite = false; snapshot = null;
+    }
+    draw();
+  }
+  async function write(action) {
+    if (!canWrite || busy) return;
+    if (action === 'resume' && (!snapshot?.halted || !UUID.test(snapshot.generation) ||
+        !window.confirm('Resume processing for this instance? New work may launch again.'))) return;
+    const args = action === 'halt' ? {} : { generation: snapshot.generation };
+    busy = true; sequence++; receipt.textContent = 'Request in progress.'; draw();
+    try {
+      const response = await fetch('/api/processing/' + action, {
+        method: 'POST', headers: { 'content-type': 'application/json' }, body: JSON.stringify(args), redirect: 'manual', cache: 'no-store',
+      });
+      const result = await response.json();
+      if (!response.ok) throw Error();
+      if (typeof result.halted !== 'boolean' || result.version !== 1 || !UUID.test(result.generation)) throw Error();
+      snapshot = result;
+      receipt.textContent = result.quiescent === false ? 'Processing is halted. Some stops are unconfirmed. Read the current status.'
+        : result.halted ? 'Processing halted.' : 'Processing resumed. Future work may launch.';
+    } catch {
+      receipt.textContent = 'Outcome unknown. Read processing status before trying again. Nothing was retried.';
+    } finally {
+      busy = false; draw(); await refresh();
+    }
+  }
+  halt.addEventListener('click', () => write('halt'));
+  resume.addEventListener('click', () => write('resume'));
+  window.addEventListener('hashchange', refresh);
+  window.addEventListener('focus', refresh);
+  setInterval(refresh, 5000);
+  refresh();
+})();

packages/webui/src/serve.mjs

@@ -9,6 +9,7 @@ import { BusReadError, busStatus as coreBusStatus, subjectOk, sendOutcome } from
 const busStatus = code => ['tester-off', 'tester-required'].includes(code) ? 403 : coreBusStatus(code);
 import { ReadError, readStatus, fieldTable } from './reads.mjs';
 import { chatHTTP } from './chat-http.mjs';
+import { processingHTTP } from './processing-http.mjs';
 
 export const DEFAULT_BOARD = 'http://127.0.0.1:7331';
 export function isLoopback(host) {
@@ -26,8 +27,8 @@ export function boardURL(value) {
 const root = resolve(import.meta.dirname, 'public');
 const files = new Map([
   ['/', ['index.html', 'text/html; charset=utf-8']],
-  ...['app.js', 'brand.js', 'bus.js', 'markdown-preview.js', 'chat.js'].map(f => ['/' + f, [f, 'text/javascript; charset=utf-8']]),
-  ...['shared/app.css', 'tokens.css', 'console.css', 'live.css', 'bus.css', 'shell.css', 'chat.css'].map(f => ['/' + f, [f, 'text/css; charset=utf-8']]),
+  ...['app.js', 'brand.js', 'bus.js', 'markdown-preview.js', 'chat.js', 'processing.js'].map(f => ['/' + f, [f, 'text/javascript; charset=utf-8']]),
+  ...['shared/app.css', 'tokens.css', 'console.css', 'live.css', 'bus.css', 'shell.css', 'chat.css', 'processing.css'].map(f => ['/' + f, [f, 'text/css; charset=utf-8']]),
   ['/editor.js', ['editor.js', 'text/javascript; charset=utf-8']],
   ['/editor.css', ['editor.css', 'text/css; charset=utf-8']],
   ['/icons.svg', ['icons.svg', 'image/svg+xml']],
@@ -472,7 +473,7 @@ async function projectFileRead(res, read, path, search) {
 // `testerNoSignIn` makes the tester listener refuse anything that looks like a sign-in (--sso). `log`
 // takes one line per send attempt that got past sign-in; never the body. `fieldsFile` is for
 // tests; the field table is otherwise the committed packages/tasks/fields.json.
-export async function startServer({ host = '127.0.0.1', port = 7330, board = DEFAULT_BOARD, timeout = 20000, bus = null, reads = null, preview = null, sso = null, tester = false, testerSocket = null, testerNoSignIn = false, testerAuthHeader = null, proof = null, testerProofHeader = null, send = null, settingsWrite = null, projectFiles = null, projectFile = null, projectSave = null, chat = null, nameWrite = null, assistantStop = null, instancesWrite = null, routesWrite = null, log = line => console.log(line), fieldsFile = undefined } = {}) {
+export async function startServer({ host = '127.0.0.1', port = 7330, board = DEFAULT_BOARD, timeout = 20000, bus = null, reads = null, preview = null, sso = null, tester = false, testerSocket = null, testerNoSignIn = false, testerAuthHeader = null, proof = null, testerProofHeader = null, send = null, settingsWrite = null, projectFiles = null, projectFile = null, projectSave = null, chat = null, nameWrite = null, assistantStop = null, instancesWrite = null, routesWrite = null, processing = null, log = line => console.log(line), fieldsFile = undefined } = {}) {
   if (!isLoopback(host)) throw new Error('refusing to bind to non-loopback host');
   if (host === 'localhost') host = '127.0.0.1';
   if (tester && preview !== null) throw new Error('tester listener cannot use preview mode');
@@ -555,6 +556,8 @@ export async function startServer({ host = '127.0.0.1', port = 7330, board = DEF
     const writer = tester ? { tester: true, user: 'tester', origin: TESTER_ORIGIN } : signer;
     if (tester && !['GET', 'HEAD'].includes(req.method) && !['/api/instances', '/api/routes', '/api/name'].includes(path) && !TESTER_CHAT_WRITE.test(path))
       return json(res, 403, { error: 'read-only', sent: false });
+    if (path === '/api/processing' || path.startsWith('/api/processing/'))
+      return processingHTTP(req, res, { path, search, processing, named, send, preview: signer });
     if(path==='/api/settings'&&req.method==='POST'){
       if(!send||!settingsWrite||!named)return json(res,403,{error:'read-only',sent:false});
       return settingsSend(req,res,{settingsWrite,preview:signer,log});

packages/webui/tests/browser.test.mjs

@@ -18,8 +18,9 @@ test('served Console browser: real board fixtures, keyboard, drafts, receipts, t
     assert.equal(await b.evaluate('document.querySelector("#session-count").textContent'), '3 of 4');
     await b.evaluate('document.querySelector("#hide-offline").click()');
     assert.equal(await b.evaluate('document.querySelectorAll("table.sessions tbody tr").length'), 4);
-    // Rows 129 and 154: chat.js and editor.js are the scripts added, same origin; the list is the pin, so another script is a visible change.
-    assert.deepEqual(await b.evaluate('[...document.querySelectorAll("script")].map(s => s.getAttribute("src"))'), ['/editor.js', '/brand.js', '/app.js', '/markdown-preview.js', '/chat.js', '/bus.js']);
+    // Rows 129, 154 and 191: the same-origin script list includes the persistent processing control.
+    assert.deepEqual(await b.evaluate('[...document.querySelectorAll("script")].map(s => s.getAttribute("src"))'), ['/editor.js', '/processing.js', '/brand.js', '/app.js', '/markdown-preview.js', '/chat.js', '/bus.js']);
+    assert.equal(await b.evaluate(`document.querySelectorAll('script[src="/processing.js"]').length`), 1);
     assert.equal(await b.evaluate(`document.querySelectorAll('script[src="/chat.js"]').length`), 1);
     assert.equal(await b.evaluate('!!window.injected'), false);
     // Project filtering does not hide another project's waiting requests.

packages/webui/tests/processing-browser.test.mjs

@@ -0,0 +1,59 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { startServer } from '../src/serve.mjs';
+import { fixture, close } from './fixture.mjs';
+import { browser } from './browser.mjs';
+const GEN = '12345678-1234-4234-8234-123456789abc';
+async function setup(t, readonly = false) {
+  const f = await fixture(); t.after(() => f.close());
+  const server = await startServer({ port: 0, board: f.boardURL }); t.after(() => close(server));
+  const b = await browser(); t.after(() => b.close());
+  await b.call('Page.addScriptToEvaluateOnNewDocument', { source: `(() => {
+    const real=fetch.bind(window);window.writes=[];window.failWrite=false;window.confirmResume=true;window.confirmed=0;
+    window.confirm=()=>{window.confirmed++;return window.confirmResume};
+    window.processing={version:1,generation:'${GEN}',halted:${readonly},quiescent:true,remaining:0,stopped:0};
+    window.fetch=async(url,init={})=>{
+      if(url==='/api/config')return new Response(JSON.stringify({send:${!readonly}}));
+      if(!String(url).startsWith('/api/processing'))return real(url,init);
+      if(init.method==='POST'){
+        window.writes.push({path:url,body:JSON.parse(init.body),redirect:init.redirect});
+        if(window.failWrite)return new Response(JSON.stringify({error:'outcome-unknown',message:'do not echo'}),{status:503});
+        window.processing.halted=String(url).endsWith('/halt');
+      }
+      return new Response(JSON.stringify(window.processing));
+    };
+  })();` });
+  await b.navigate(`http://127.0.0.1:${server.address().port}/`);
+  const wait = expression => b.evaluate(`(async()=>{for(let i=0;i<100;i++){if(${expression})return;await new Promise(r=>setTimeout(r,30));}throw Error(${JSON.stringify(expression)})})()`);
+  await wait(`document.querySelector('#processing-state')?.textContent.includes(${JSON.stringify(readonly ? 'halted' : 'enabled')})`);
+  return { b, wait };
+}
+test('processing browser: keyboard Stop, confirmed Resume, unknown outcome and persistent banner', async t => {
+  const { b, wait } = await setup(t);
+  await b.evaluate(`document.querySelector('#processing-halt').focus(),true`); await b.key('Enter');
+  await wait('window.writes.length===1 && !document.querySelector("#processing-banner").hidden');
+  assert.deepEqual(await b.evaluate('window.writes[0]'), { path: '/api/processing/halt', body: {}, redirect: 'manual' });
+  for (const route of ['#/tasks', '#/settings', '#/board']) {
+    await b.evaluate(`location.hash=${JSON.stringify(route)},true`);
+    assert.equal(await b.evaluate('document.querySelector("#processing-banner").hidden'), false);
+  }
+  await b.evaluate('window.confirmResume=false;document.querySelector("#processing-resume").click();true');
+  assert.equal(await b.evaluate('window.writes.length'), 1);
+  await b.evaluate('window.confirmResume=true;document.querySelector("#processing-resume").click();true');
+  await wait('window.writes.length===2 && document.querySelector("#processing-banner").hidden');
+  assert.deepEqual(await b.evaluate('window.writes[1].body'), { generation: GEN });
+  assert.equal(await b.evaluate('window.confirmed'), 2);
+  await b.evaluate('window.failWrite=true;document.querySelector("#processing-halt").click();true');
+  await wait('document.querySelector("#processing-receipt").textContent.includes("Outcome unknown")');
+  assert.equal(await b.evaluate('window.writes.length'), 3);
+  assert.doesNotMatch(await b.evaluate('document.querySelector("#processing-receipt").textContent'), /do not echo/);
+});
+test('processing browser: Q175 read-only interim keeps both writes disabled and names CLI recovery at 320px', async t => {
+  const { b, wait } = await setup(t, true); await b.viewport(320);
+  assert.equal(await b.evaluate('document.querySelector("#processing-halt").disabled'), true);
+  assert.equal(await b.evaluate('document.querySelector("#processing-resume").disabled'), true);
+  assert.match(await b.evaluate('document.querySelector("#processing-unavailable").textContent'), /mosaic halt.*mosaic resume/);
+  await b.evaluate('document.querySelector("#processing-halt").click();document.querySelector("#processing-resume").click();true');
+  assert.equal(await b.evaluate('window.writes.length'), 0);
+  assert.equal(await b.evaluate('document.querySelector("#processing-banner").hidden'), false);
+});

packages/webui/tests/processing-ui.test.mjs

@@ -0,0 +1,68 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { readFileSync } from 'node:fs';
+import { runInNewContext } from 'node:vm';
+const source = new URL('../src/public/processing.js', import.meta.url);
+const GEN = '12345678-1234-4234-8234-123456789abc';
+const flush = async () => { for (let i = 0; i < 8; i++) await new Promise(resolve => setImmediate(resolve)); };
+async function fixture({ send = true, halted = false, unknown = false, partial = false, confirm = true } = {}) {
+  const nodes = new Map(), requests = [], events = new Map(); let confirmations = 0;
+  for (const id of ['processing-controls', 'processing-state', 'processing-halt', 'processing-resume', 'processing-unavailable', 'processing-receipt', 'processing-banner'])
+    nodes.set(id, { id, hidden: false, disabled: false, textContent: '', dataset: {}, listeners: new Map(), addEventListener(name, fn) { this.listeners.set(name, fn); } });
+  const state = { version: 1, generation: GEN, halted, quiescent: !partial, remaining: partial ? 1 : 0, stopped: 0 };
+  runInNewContext(readFileSync(source, 'utf8'), {
+    document: { getElementById: id => nodes.get(id) },
+    window: { addEventListener: (name, fn) => events.set(name, fn), confirm: () => { confirmations++; return confirm; } },
+    setInterval: () => ({ unref() {} }), clearInterval() {},
+    fetch: async (url, options = {}) => {
+      requests.push({ url, ...options });
+      if (url === '/api/config') return { ok: true, json: async () => ({ send }) };
+      if (options.method === 'POST') {
+        if (unknown) return { ok: false, json: async () => ({ error: 'outcome-unknown', message: 'untrusted backend text' }) };
+        state.halted = url.endsWith('/halt');
+        return { ok: true, json: async () => ({ ...state }) };
+      }
+      return { ok: true, json: async () => ({ ...state }) };
+    },
+  });
+  await flush();
+  const click = async id => { await nodes.get(id).listeners.get('click')(); await flush(); };
+  return { nodes, requests, events, state, click, confirmations: () => confirmations };
+}
+test('interim read-only controls show CLI recovery, disable both writes and retain a halted banner across views', async () => {
+  const f = await fixture({ send: false, halted: true });
+  assert.equal(f.nodes.get('processing-halt').disabled, true); assert.equal(f.nodes.get('processing-resume').disabled, true);
+  assert.match(f.nodes.get('processing-unavailable').textContent, /mosaic halt.*mosaic resume/);
+  assert.equal(f.nodes.get('processing-banner').hidden, false);
+  await f.events.get('hashchange')(); await flush();
+  assert.equal(f.nodes.get('processing-banner').hidden, false);
+  assert.equal(f.requests.filter(r => r.method === 'POST').length, 0);
+});
+test('Stop sends one empty halt and Resume confirms before sending the displayed generation', async () => {
+  const f = await fixture(); await f.click('processing-halt');
+  assert.equal(f.nodes.get('processing-banner').hidden, false);
+  await f.click('processing-resume'); assert.equal(f.confirmations(), 1);
+  const writes = f.requests.filter(r => r.method === 'POST');
+  assert.deepEqual(writes.map(r => [r.url, JSON.parse(r.body)]), [['/api/processing/halt', {}], ['/api/processing/resume', { generation: GEN }]]);
+  assert.ok(writes.every(r => r.headers['content-type'] === 'application/json'));
+});
+test('a cancelled resume never calls the writer', async () => {
+  const f = await fixture({ halted: true, confirm: false }); await f.click('processing-resume');
+  assert.equal(f.requests.filter(r => r.method === 'POST').length, 0);
+});
+test('unknown writes are not retried or displayed as success and partial stops remain explicit', async () => {
+  const f = await fixture({ unknown: true }); await f.click('processing-halt');
+  assert.equal(f.requests.filter(r => r.method === 'POST').length, 1);
+  assert.match(f.nodes.get('processing-receipt').textContent, /Outcome unknown/);
+  assert.doesNotMatch(f.nodes.get('processing-receipt').textContent, /untrusted backend text|Processing halted\./);
+  const partial = await fixture({ partial: true }); await partial.click('processing-halt');
+  assert.match(partial.nodes.get('processing-receipt').textContent, /unconfirmed/);
+});
+test('the persistent shell loads the control outside route-specific content with accessible status and native buttons', () => {
+  const html = readFileSync(new URL('../src/public/index.html', import.meta.url), 'utf8');
+  assert.ok(html.indexOf('id="processing-controls"') < html.indexOf('<div class="frame">'));
+  assert.match(html, /src="\/processing.js"/); assert.match(html, /href="\/processing.css"/);
+  assert.match(html, /id="processing-receipt"[^>]*aria-live="polite"/);
+  assert.match(html, /<button[^>]*id="processing-halt"[^>]*type="button"/);
+  assert.match(html, /<button[^>]*id="processing-resume"[^>]*type="button"/);
+});

packages/webui/tests/processing.test.mjs

@@ -0,0 +1,83 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { request } from 'node:http';
+import { startServer } from '../src/serve.mjs';
+import { close } from './fixture.mjs';
+const GEN = '12345678-1234-4234-8234-123456789abc';
+function http(server, path, { method = 'GET', headers = {}, body = '' } = {}) {
+  return new Promise((resolve, reject) => {
+    const req = request({ host: '127.0.0.1', port: server.address().port, path, method,
+      headers: Object.fromEntries(Object.entries({ host: 'console.example', 'x-user': 'jason', ...headers }).filter(([, v]) => v !== undefined)) }, res => {
+      let text = ''; res.on('data', c => { text += c; }); res.on('end', () => resolve({ status: res.statusCode, text, value: JSON.parse(text) }));
+    }); req.on('error', reject); req.end(body);
+  });
+}
+const POST = { method: 'POST', headers: { origin: 'https://console.example', 'sec-fetch-site': 'same-origin', 'content-type': 'application/json' }, body: '{}' };
+async function fixture(t, { send = true, tester = false } = {}) {
+  const calls = [];
+  const state = { version: 1, generation: GEN, halted: false, quiescent: true, remaining: 0, stopped: 0, stopping: false };
+  const processing = {
+    read: async () => { calls.push('read'); return { ...state }; },
+    halt: async args => { calls.push(['halt', args]); state.halted = true; return { ...state }; },
+    resume: async args => { calls.push(['resume', args]); state.halted = false; return { ...state }; },
+  };
+  const server = await startServer({ port: 0, ...(tester ? { tester: true } : { preview: { host: 'console.example', header: 'x-user', user: 'jason' } }),
+    send: send && !tester ? async () => {} : null, processing, log: () => {} });
+  t.after(() => close(server)); return { server, calls, state, processing };
+}
+test('read-only Console can read processing state but neither human control writes without --send', async t => {
+  const f = await fixture(t, { send: false });
+  const read = await http(f.server, '/api/processing'); assert.equal(read.status, 200); assert.equal(read.value.halted, false);
+  for (const action of ['halt', 'resume']) assert.equal((await http(f.server, '/api/processing/' + action, POST)).status, 403);
+  assert.deepEqual(f.calls, ['read']);
+});
+test('Console halt and generation-bound resume use only the management writer and keep partial stops honest', async t => {
+  const f = await fixture(t);
+  const halted = await http(f.server, '/api/processing/halt', POST); assert.equal(halted.status, 200); assert.equal(halted.value.halted, true);
+  const resumed = await http(f.server, '/api/processing/resume', { ...POST, body: JSON.stringify({ generation: GEN }) });
+  assert.equal(resumed.status, 200); assert.equal(resumed.value.halted, false);
+  assert.deepEqual(f.calls, [['halt', {}], ['resume', { generation: GEN }]]);
+  f.processing.halt = async () => ({ ...f.state, halted: true, quiescent: false, remaining: 1 });
+  const partial = await http(f.server, '/api/processing/halt', POST); assert.equal(partial.status, 202); assert.equal(partial.value.quiescent, false);
+});
+test('processing write fences refuse cross-site, wrong origin, unnamed host, duplicate identity and bad payload before writer', async t => {
+  const f = await fixture(t);
+  const cases = [
+    { headers: { ...POST.headers, origin: 'https://elsewhere' } },
+    { headers: { ...POST.headers, 'sec-fetch-site': 'cross-site' } },
+    { headers: { ...POST.headers, host: `127.0.0.1:${f.server.address().port}`, 'x-user': undefined } },
+    { headers: { ...POST.headers, 'x-user': ['jason', 'jason'] } },
+    { headers: { ...POST.headers, 'content-type': 'text/plain' } },
+    { body: '{"human":"jason"}' }, { body: '[]' }, { body: 'null' }, { body: ' '.repeat(1025) },
+  ];
+  for (const c of cases) assert.ok((await http(f.server, '/api/processing/halt', { ...POST, ...c })).status >= 400);
+  assert.equal((await http(f.server, '/api/processing/resume', POST)).status, 400);
+  assert.deepEqual(f.calls, []);
+});
+test('tester cannot invoke either control writer and failures never echo backend text', async t => {
+  const f = await fixture(t, { tester: true });
+  const headers = { host: `127.0.0.1:${f.server.address().port}` };
+  for (const action of ['halt', 'resume']) assert.equal((await http(f.server, '/api/processing/' + action, { ...POST, headers: { ...POST.headers, ...headers } })).status, 403);
+  assert.deepEqual(f.calls, []);
+  const human = await fixture(t); human.processing.halt = async () => { throw Object.assign(Error('NEVER ECHO fixture path'), { code: 'outcome-unknown' }); };
+  const r = await http(human.server, '/api/processing/halt', POST);
+  assert.equal(r.status, 503); assert.equal(r.value.sent, 'unknown'); assert.doesNotMatch(r.text, /NEVER ECHO/);
+});
+
+// Rebase on row 192: the server verifies the cookie before passing its signer.
+test('processing writes use the existing SSO signer and still require --send and same-origin', async t => {
+  for (const enabled of [false, true]) {
+    const calls = [];
+    const sso = { formTargets: () => [], publicHost: 'console.example', publicOrigin: 'https://console.example',
+      session: req => req.headers.cookie === 'fixture=authenticated' ? { name: 'jason' } : null };
+    const state = { version: 1, generation: GEN, halted: true, quiescent: true };
+    const server = await startServer({ port: 0, sso, send: enabled ? async () => {} : null,
+      processing: { halt: async () => { calls.push('halt'); return state; } } });
+    t.after(() => close(server));
+    const headers = { ...POST.headers, cookie: 'fixture=authenticated', 'x-user': undefined };
+    assert.equal((await http(server, '/api/processing/halt', { ...POST, headers })).status, enabled ? 200 : 403);
+    assert.equal((await http(server, '/api/processing/halt', { ...POST, headers: { ...headers, cookie: undefined } })).status, 401);
+    assert.equal((await http(server, '/api/processing/halt', { ...POST, headers: { ...headers, origin: 'https://elsewhere' } })).status, 403);
+    assert.deepEqual(calls, enabled ? ['halt'] : []);
+  }
+});

scripts/agent.sh

@@ -53,6 +53,7 @@ case "$NAME" in *[!A-Za-z0-9._-]*|'') echo "agent: invalid agent name" >&2; exit
 load_config
 load_release
 bootstrap_runtime_dir
+processing_guard
 ensure_release_aligned
 
 # Named auth account (M19, corrected per owner in #48): per-launch
@@ -205,4 +206,4 @@ export MOSAIC_WORKSPACE="/var/lib/mosaic/workspaces/$WORKSPACE"
 echo "agent: launching TUI agent '$NAME' (session: $SESSION, adapter: $MOSAIC_ADAPTER, model: $MOSAIC_MODEL)"
 echo "agent: contracts + $([ -n "$MISSION" ] && echo 'mission' || echo 'no mission') loaded; exit the TUI with /quit"
 # No -T: the TTY is the point. Ctrl+C twice or /quit exits.
-exec docker compose run --rm mosaic-agent
+exec node packages/processing-control/src/container-cli.mjs --tty

scripts/common.sh

@@ -2,6 +2,11 @@
 
 POC_ROOT_MARKER=".mosaic-poc-root"
 
+# Trusted first initialization plus a fresh processing check, before credentials/build/network work.
+processing_guard() {
+    node packages/processing-control/src/container-cli.mjs --check
+}
+
 # Load and validate the Mosaic configuration (config.json), exporting
 # MOSAIC_DATA_ROOT, MOSAIC_PROVIDER, and MOSAIC_MODEL.
 #

scripts/hello.sh

@@ -14,6 +14,7 @@ load_config
 load_release
 
 bootstrap_runtime_dir
+processing_guard
 ensure_release_aligned
 
 # -T: no pseudo-TTY, so stdout is clean model output.
@@ -21,4 +22,4 @@ ensure_release_aligned
 # an interactive terminal would otherwise block it forever. The request
 # text comes from the compose command, not stdin, so nothing is lost.
 # Errors, if any, go to stderr for diagnostics.
-docker compose run --rm -T mosaic-agent < /dev/null
+node packages/processing-control/src/container-cli.mjs < /dev/null

scripts/mosaic

@@ -41,6 +41,6 @@ if [ "${1:-}" = library ] && [ "${2:-}" = survey ]; then
   exec node "$REPO/packages/library/src/survey.mjs" "$@"
 fi
 case "${1:-}" in
-  usage|project|limits|inbox|decide|tasks|agents|trail|talk|stop|launches|bus|plugins|credentials|hosts|name|names|follow|threads|thread|access) exec node "$REPO/packages/cli/src/cli.mjs" "$@" ;;
+  halt|resume|processing|usage|project|limits|inbox|decide|tasks|agents|trail|talk|stop|launches|bus|plugins|credentials|hosts|name|names|follow|threads|thread|access) exec node "$REPO/packages/cli/src/cli.mjs" "$@" ;;
 esac
 exec node "$REPO/packages/seat/src/cli.mjs" "$@"

scripts/mosaic-task.mjs

@@ -36,6 +36,9 @@ import { spawnSync } from "node:child_process";
 import { fileURLToPath } from "node:url";
 import { BusinessError, validateRoleDocument } from "../packages/business/src/index.mjs";
 import { RunsError, isRunId, listRunRecords, readRunRecord } from "../packages/runs/src/index.mjs";
+import { initializeControl, assertProcessing } from "../packages/processing-control/src/state.mjs";
+import { runContainer } from "../packages/processing-control/src/containers.mjs";
+import { unregisterRuntime } from "../packages/processing-control/src/runtimes.mjs";
 
 const PROJECT_ROOT = path.resolve(path.dirname(fileURLToPath(import.meta.url)), "..");
 const RUNS_DIRNAME = "runs";
@@ -298,6 +301,8 @@ function runTask(taskFile, options = {}) {
       maxBuffer: 1024 * 1024,
     }).stdout,
   );
+  try { initializeControl(resolved.dataRoot); assertProcessing(resolved.dataRoot); }
+  catch (e) { fail(3, e.code?.startsWith('processing-') ? e.code : 'processing-state-invalid'); }
 
   const task = validateTask(readJsonFile(taskFile, "task file"), path.resolve(taskFile));
   const runId = `r-${utcStamp()}-${randomBytes(3).toString("hex")}`;
@@ -392,10 +397,10 @@ function runTask(taskFile, options = {}) {
     spawnEnv.MOSAIC_SESSION_FORK = `/var/lib/mosaic/${relative.split(path.sep).join("/")}`;
   }
 
-  const proc = spawnSync(
-    "docker",
-    ["compose", "run", "--rm", "-T", "mosaic-agent", task.prompt],
-    {
+  let launched;
+  try {
+    launched = runContainer(resolved.dataRoot, { kind: 'task', business: 'instance', run: runId }, {
+      args: [task.prompt],
       cwd: PROJECT_ROOT,
       env: spawnEnv,
       input: "", // stdin detached: print mode must never wait on a terminal (see issue #5)
@@ -403,8 +408,9 @@ function runTask(taskFile, options = {}) {
       maxBuffer: 16 * 1024 * 1024,
       timeout: task.timeoutSeconds * 1000,
       killSignal: "SIGKILL",
-    },
-  );
+    });
+  } catch (e) { fail(3, e.code?.startsWith('processing-') ? e.code : 'processing-container-failed'); }
+  const { proc, managed, haltGeneration } = launched;
   const finishedAt = new Date();
 
   fs.writeFileSync(stderrFile, proc.stderr ?? "", { flag: "wx" });
@@ -427,6 +433,7 @@ function runTask(taskFile, options = {}) {
     status = "failed";
     reason = "expect-mismatch";
   }
+  if (haltGeneration) { status = 'failed'; reason = 'kill-switch'; }
 
   const result = {
     runVersion: 1,
@@ -435,6 +442,7 @@ function runTask(taskFile, options = {}) {
     missionId: task.missionId,
     status,
     reason,
+    ...(haltGeneration ? { haltGeneration } : {}),
     request: task.prompt,
     response,
     expectedExact: expected,
@@ -453,6 +461,7 @@ function runTask(taskFile, options = {}) {
   };
 
   writeOnce(path.join(runDir, "result.json"), `${JSON.stringify(result, null, 2)}\n`);
+  if (!haltGeneration && !proc.error && proc.status === 0) unregisterRuntime(resolved.dataRoot, managed.id);
 
   process.stdout.write(`run: ${runId}\nstatus: ${status}${reason ? ` (${reason})` : ""}\nresponse: ${response}\n`);
   process.exit(status === "succeeded" ? 0 : 1);

scripts/run-task.sh

@@ -13,6 +13,7 @@ source scripts/common.sh
 load_config
 load_release   # compose requires MOSAIC_IMAGE_TAG; task runs are release-scoped too
 bootstrap_runtime_dir
+processing_guard
 
 # Workers never auto-align releases (no builds or model gates mid-automation);
 # drift is reported so the operator or a human-facing launcher can align.

scripts/stack-copy.sh

@@ -32,6 +32,7 @@ COPY_PATHS=(
  packages/bus/src packages/bus/schema.sql packages/business/src packages/cli/src packages/project
  packages/conversation/src packages/discord/src packages/discord/bin packages/discord/extension packages/harness/src
  packages/seat/src packages/tasks/src packages/tasks/fields.json packages/tasks/requirements.json
+ packages/processing-control
  packages/webui/src packages/webui/README.md packages/cli/README.md
  packages/queue/src packages/library/src packages/library/bin
  # Whole directory: every in-repo plug-in module ships with the copy (row 131).

scripts/verify.sh

@@ -30,6 +30,7 @@ IMAGE="$MOSAIC_IMAGE_TAG"
 # Ensure the configured data root exists (host-owned) before the mount,
 # otherwise Docker would auto-create a root-owned directory.
 bootstrap_runtime_dir
+processing_guard
 ensure_release_aligned
 
 # 1. Build the image only if it is not already present.
@@ -42,7 +43,7 @@ fi
 # 2. Run the agent request (stdout only = model response).
 # stdin detached: see hello.sh — print mode would block on a terminal.
 set +e
-RESPONSE="$(docker compose run --rm -T mosaic-agent </dev/null 2>/tmp/mosaic-poc-stderr.$$)"
+RESPONSE="$(node packages/processing-control/src/container-cli.mjs </dev/null 2>/tmp/mosaic-poc-stderr.$$)"
 RC=$?
 set -e
 STDERR_FILE="/tmp/mosaic-poc-stderr.$$"

src/run-agent.sh

@@ -9,6 +9,7 @@
 # but the adapter opens the full pi TUI with no initial prompt - the human
 # drives from there.
 set -eu
+node /opt/mosaic/processing-control/entrypoint.mjs /var/lib/mosaic
 
 REQUEST=""
 if [ "${MOSAIC_INTERACTIVE:-}" != "1" ]; then