threadsState gives one row per session with `session` and `legacy`; threadIdle
idles a run against its bound session. Each session gets its own store
(threads/<b>/<t>/sessions/<s>/, or the thread's old store for a legacy-3l
session) and its own workspace (session-workspaces/<b>/<i>/<s>/), held by an
O_EXCL <ws>.lock from before the clones to the run's proven exit. A legacy
session's workspace binds in-sandbox at the old instance path. sessions.json
is v2 and reads v1. New tests: cli session-launch.test.mjs, seat
session-workspace.test.mjs. Not yet run: tests wait for Sage's CLEAR.
Two old assertions change as exact updates:
- mos-1285: end-launch.test.mjs threadsState deepEqual. The old row shape was
{ thread: 'th-1', instance: 'coder', pending: 0, unread: 0, lastMessage: null,
lastOpen: '2026-10-15T00:00:01.000Z', lastClaim: null, holder: null }; the
row keeps every key and value and adds session: 'th-1', legacy: true.
- mos-1289: thread-launch.test.mjs:182, old line
`const store = join(f.dataRoot, "threads", "acme", A);`
now reads A's default session id from threadsState's `session` key; :183-185
unchanged; one added assert that threads/acme/<A>/session is absent.
sessions and session_defaults are new and append-only. thread_claims, message_threads and
thread_opens are rebuilt in place with a session column, and thread_claims gains a generation
counted from claim rows. Each existing thread gets a default session with the thread's id; new
threads get a random one. Holder, per-run, release and delivery triggers key on the session,
and two id triggers keep session and thread ids apart (Duckworth checks 1-7, duckworth-0106).
The broker binds a thread run to a session (the default when the record names none), and
thread.open, thread.send and thread.messages take an optional session. New verbs session.list
and session.create (idempotent on op). Tests: sessions.test.mjs for T1 bus half, T2 and T7 with
a pinned 3k fixture; count, version and verb pins; hand-made test threads write the legacy
default session.
Built on row 236 (8f51900b5), which takes 3j-3k, so this step is 3k-3l by landing order
(row264 Q2, sage-2412). The op values are legacy-3l and migration-3l. gitea-migration.test reads
its store after both steps. Not run yet: every run waits for Sage's CLEAR.
Adds the harness plug-in kind (interface 1). packages/plugins/harness/pi
and claude-code hold what core branched on: the adapter, thinking levels,
preflight, version probe, sandbox mounts, builtins line, typed tool names,
gate timeout, bundle files, adapter env, turn end and session-files path.
Core reaches a module only through the loader.
A session's route is the instance's harness, model and thinking vars, or
the three fallback. vars; a missing one refuses no-route, and the system
file's execution keys are never read for a session. The launcher checks
the primary route, then the fallback: harness-off, harness-refused,
thinking-unsupported, then preflight. A failed preflight falls back when
a fallback is set, and any refusal of the fallback names the primary's
failure too. Account checks run
only when the route's module counts an account. The manifest records
route, routeReason and harnessVersion, replacing piVersion and
claudeVersion. pi gets --thinking, Claude Code --effort, both from
MOSAIC_THINKING.
The business file refuses a partial fallback. routes and routes.set are
human-only bus verbs outside ORGANIZATION_KEYS; checkRoutes is shared by
routes.set, instances.set and limits.set and checks only changed routes.
The chief of staff changes an instance's model, and the assistant's whole
vars (Q169), through limits.set, so its route write runs the same checks.
A model outside launch.models refuses unknown-model, primary or fallback,
and routes.set passes that code through.
A new run binds only on a switched-on harness module name and records
its transcript path, which the usage reader uses. Settings gains a
Routing table with six selects per instance and loses the Role models
fieldset; it posts changed rows to /api/routes. webui/src/bus.mjs is
unchanged.
Until Jason's `mosaic plugins set` adds "harness": ["claude-code"], a new
launch refuses harness-off.
Darkwing's row 121 round 2 (agents/darkwing/work/queue-121/r2, base
20d2b5788, manifest 710d5086...e67e9b, 30 files), applied unchanged on
d7ebaa9a5; no commit since the base touches any of the 30 paths. Dewey
asked for changes on round 1 in comment 28591 (F1 to F6) and approved
round 2 in 28615. Landing gate on d7ebaa9a5 plus the candidate: all 24
suites passed, 0 failed.
F6 and Dewey's three round 2 notes are follow-ups (sage-0369, P19 task
311). One of them corrects the packet: BUILD.md says the decision-route
setup's projects key is needed, and Dewey's probe showed project.create
reads it only with repo, so the key is dead setup.
The live bus stays at 3b until Mos's schema window migrates it.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Slice 1 S6. packages/harness runs a role session under the pi or claude
adapter behind a tool gate, and packages/seat holds the session and its
process. The bus host gains a launch socket: `mosaic bus start
<business> --pm <harness>:<model>` runs the PM without a window, the PM
launches role sessions through the broker within the business file's
`launch.max`, and every launch, refusal and end is a launch-log line and
a broker event. `mosaic talk`, `mosaic launches off|on|list` and
`mosaic stop <run>` are new CLI verbs. packages/bus gains the IPC ops
identity, authorize, refuse, endLaunch and credentialStatus, plus
Broker.endLaunch (decision 77); no socket verb, event kind or schema
changed. The session environment is an allowlist, and the runner exits
before claiming if a founder credential reaches it.
Filbert built it (agents/filbert/work/s6). Darkwing reviewed on #1523:
round 1 changes (26991/26995), round 2 changes (27004/27010), round 3
changes (27012/27032), round 4 approve (27033/27034) on manifest
08a78972, 42 paths.
Sage's gate on 64b0f9f1 (12:32Z), sequential and teed: node suites
business 60, bus 74, cli 83, control-board 124, conversation 182,
discord 178, harness 56, ledger 78, mosaic 69, queue 149, runs 41,
seat 27, tasks 51, webui 39, every one 0 failed; test-auth 15,
test-conductor 17, test-config 24, test-discord 66,
test-extension-package 18, test-foundation 44, test-queue 27,
test-release 14, test-task 98 and 26 without Docker, all 0 failed.
64b0f9f1..ee7f909b touches none of the 42 paths. It landed after the
Q14 hold ended at 2026-10-11T17:19:23.857Z. The recorded PM-to-coder
run on a scratch data root is still owed before row 41 moves to done.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
jason.woltje
