feat(pi): add persistent Mosaic /goal controller (#1152)

packages/mosaic/src/commands/launch.spec.ts

@@ -5,6 +5,7 @@ import { tmpdir } from 'node:os';
 import { join } from 'node:path';
 import {
   buildPiSkillArgs,
+  discoverPiExtensionArgs,
   enumerateSkillDirs,
   piForceSkillNames,
   registerRuntimeLaunchers,
@@ -178,6 +179,52 @@ describe('buildPiSkillArgs', () => {
   });
 });
 
+describe('discoverPiExtensionArgs', () => {
+  it('loads the core and goal extensions in deterministic order from Mosaic home', () => {
+    const root = mkdtempSync(join(tmpdir(), 'mosaic-pi-extensions-'));
+    const runtimeDir = join(root, 'runtime', 'pi');
+    mkdirSync(runtimeDir, { recursive: true });
+    writeFileSync(join(runtimeDir, 'goal-extension.ts'), '// goal\n');
+    writeFileSync(join(runtimeDir, 'mosaic-extension.ts'), '// core\n');
+
+    try {
+      expect(discoverPiExtensionArgs(root)).toEqual([
+        '--extension',
+        join(runtimeDir, 'mosaic-extension.ts'),
+        '--extension',
+        join(runtimeDir, 'goal-extension.ts'),
+      ]);
+    } finally {
+      rmSync(root, { recursive: true, force: true });
+    }
+  });
+
+  it('remains backward-compatible when the optional goal extension is absent', () => {
+    const root = mkdtempSync(join(tmpdir(), 'mosaic-pi-extensions-'));
+    const runtimeDir = join(root, 'runtime', 'pi');
+    mkdirSync(runtimeDir, { recursive: true });
+    writeFileSync(join(runtimeDir, 'mosaic-extension.ts'), '// core\n');
+
+    try {
+      expect(discoverPiExtensionArgs(root)).toEqual([
+        '--extension',
+        join(runtimeDir, 'mosaic-extension.ts'),
+      ]);
+    } finally {
+      rmSync(root, { recursive: true, force: true });
+    }
+  });
+
+  it('emits no extension arguments when Mosaic runtime assets are absent', () => {
+    const root = mkdtempSync(join(tmpdir(), 'mosaic-pi-extensions-'));
+    try {
+      expect(discoverPiExtensionArgs(root)).toEqual([]);
+    } finally {
+      rmSync(root, { recursive: true, force: true });
+    }
+  });
+});
+
 describe('enumerateSkillDirs (real FS)', () => {
   let root: string;
 

packages/mosaic/src/commands/launch.ts

@@ -715,9 +715,15 @@ export function buildPiSkillArgs(
   return ['--no-skills', ...forcedSkillArgs];
 }
 
-function discoverPiExtension(): string[] {
-  const ext = join(MOSAIC_HOME, 'runtime', 'pi', 'mosaic-extension.ts');
-  return existsSync(ext) ? ['--extension', ext] : [];
+const PI_EXTENSION_FILES = ['mosaic-extension.ts', 'goal-extension.ts'] as const;
+
+export function discoverPiExtensionArgs(mosaicHome: string = MOSAIC_HOME): string[] {
+  const args: string[] = [];
+  for (const fileName of PI_EXTENSION_FILES) {
+    const extensionPath = join(mosaicHome, 'runtime', 'pi', fileName);
+    if (existsSync(extensionPath)) args.push('--extension', extensionPath);
+  }
+  return args;
 }
 
 // ─── Launch functions ────────────────────────────────────────────────────────
@@ -792,7 +798,7 @@ function launchRuntime(runtime: RuntimeName, args: string[], yolo: boolean): nev
       const prompt = buildRuntimePrompt('pi');
       const cliArgs = ['--append-system-prompt', prompt];
       cliArgs.push(...buildPiSkillArgs(args));
-      cliArgs.push(...discoverPiExtension());
+      cliArgs.push(...discoverPiExtensionArgs());
       if (hasMissionNoArgs) {
         cliArgs.push(missionPrompt);
       } else {

packages/mosaic/src/config/file-adapter.test.ts

@@ -209,6 +209,20 @@ describe('FileConfigAdapter.syncFramework — defaults seeding', () => {
     );
   });
 
+  it('deploys the Mosaic-owned Pi goal extension only inside the Mosaic runtime tree', async () => {
+    const sourceRuntime = join(fixture.sourceDir, 'runtime', 'pi');
+    mkdirSync(sourceRuntime, { recursive: true });
+    writeFileSync(join(sourceRuntime, 'goal-extension.ts'), '// persistent goal extension\n');
+
+    const adapter = new FileConfigAdapter(fixture.mosaicHome, fixture.sourceDir);
+    await adapter.syncFramework('fresh');
+
+    expect(
+      readFileSync(join(fixture.mosaicHome, 'runtime', 'pi', 'goal-extension.ts'), 'utf-8'),
+    ).toBe('// persistent goal extension\n');
+    expect(existsSync(join(fixture.mosaicHome, '.pi'))).toBe(false);
+  });
+
   it('is a no-op for seeding when defaults/ dir does not exist', async () => {
     rmSync(fixture.defaultsDir, { recursive: true });
 

packages/mosaic/src/runtime/pi-goal-extension.spec.ts

@@ -0,0 +1,796 @@
+import { afterEach, describe, expect, it, vi } from 'vitest';
+
+interface FakeEntry {
+  type: string;
+  customType?: string;
+  data?: unknown;
+}
+
+interface SentMessage {
+  message: {
+    customType: string;
+    content: string;
+    display: boolean;
+  };
+  options?: {
+    triggerTurn?: boolean;
+    deliverAs?: 'steer' | 'followUp' | 'nextTurn';
+  };
+}
+
+interface FakeContext {
+  cwd: string;
+  ui: {
+    notifications: Array<{ message: string; level?: string }>;
+    statuses: Map<string, string | undefined>;
+    notify(message: string, level?: string): void;
+    setStatus(key: string, value: string | undefined): void;
+  };
+  sessionManager: {
+    getBranch(): FakeEntry[];
+  };
+  isIdle(): boolean;
+  hasPendingMessages(): boolean;
+  abort(): void;
+}
+
+type EventHandler = (
+  event: Record<string, unknown>,
+  context: FakeContext,
+) => unknown | Promise<unknown>;
+
+type CommandHandler = (args: string, context: FakeContext) => unknown | Promise<unknown>;
+
+interface FakeToolResult {
+  content: Array<{ type: string; text: string }>;
+  details?: unknown;
+  terminate?: boolean;
+}
+
+interface FakeTool {
+  name: string;
+  execute(
+    toolCallId: string,
+    params: Record<string, unknown>,
+    signal: AbortSignal | undefined,
+    onUpdate: undefined,
+    context: FakeContext,
+  ): Promise<FakeToolResult>;
+}
+
+interface GoalExtensionFactory {
+  (api: FakePiApi): void;
+}
+
+interface GoalExtensionModule {
+  default: GoalExtensionFactory;
+}
+
+interface FakePiApi {
+  on(event: string, handler: EventHandler): void;
+  registerCommand(name: string, options: { description: string; handler: CommandHandler }): void;
+  registerTool(tool: FakeTool): void;
+  appendEntry(customType: string, data?: unknown): void;
+  sendMessage(message: SentMessage['message'], options?: SentMessage['options']): void;
+}
+
+function isGoalExtensionModule(value: unknown): value is GoalExtensionModule {
+  if (typeof value !== 'object' || value === null) return false;
+  return typeof Reflect.get(value, 'default') === 'function';
+}
+
+const goalExtensionUrl = new URL('../../framework/runtime/pi/goal-extension.ts', import.meta.url)
+  .href;
+const importedGoalExtension: unknown = await import(goalExtensionUrl);
+if (!isGoalExtensionModule(importedGoalExtension)) {
+  throw new Error('Pi goal extension must export a default registration function');
+}
+const registerGoalExtension = importedGoalExtension.default;
+
+function isRecord(value: unknown): value is Record<string, unknown> {
+  return typeof value === 'object' && value !== null && !Array.isArray(value);
+}
+
+class FakePi {
+  readonly handlers = new Map<string, EventHandler[]>();
+  readonly commands = new Map<string, CommandHandler>();
+  readonly tools = new Map<string, FakeTool>();
+  readonly entries: FakeEntry[] = [];
+  readonly sentMessages: SentMessage[] = [];
+  readonly notifications: Array<{ message: string; level?: string }> = [];
+  readonly statuses = new Map<string, string | undefined>();
+  branch: FakeEntry[] = [];
+  idle = true;
+  pending = false;
+  abortCount = 0;
+
+  readonly context: FakeContext = {
+    cwd: '/tmp/project',
+    ui: {
+      notifications: this.notifications,
+      statuses: this.statuses,
+      notify: (message: string, level?: string): void => {
+        this.notifications.push({ message, level });
+      },
+      setStatus: (key: string, value: string | undefined): void => {
+        this.statuses.set(key, value);
+      },
+    },
+    sessionManager: {
+      getBranch: (): FakeEntry[] => [...this.branch],
+    },
+    isIdle: (): boolean => this.idle,
+    hasPendingMessages: (): boolean => this.pending,
+    abort: (): void => {
+      this.abortCount += 1;
+    },
+  };
+
+  readonly api: FakePiApi = {
+    on: (event: string, handler: EventHandler): void => {
+      this.handlers.set(event, [...(this.handlers.get(event) ?? []), handler]);
+    },
+    registerCommand: (
+      name: string,
+      options: { description: string; handler: CommandHandler },
+    ): void => {
+      this.commands.set(name, options.handler);
+    },
+    registerTool: (tool: FakeTool): void => {
+      this.tools.set(tool.name, tool);
+    },
+    appendEntry: (customType: string, data?: unknown): void => {
+      const entry: FakeEntry = { type: 'custom', customType, data };
+      this.entries.push(entry);
+      this.branch.push(entry);
+    },
+    sendMessage: (message: SentMessage['message'], options?: SentMessage['options']): void => {
+      this.sentMessages.push({ message, options });
+    },
+  };
+
+  constructor(initialBranch: FakeEntry[] = []) {
+    this.branch = [...initialBranch];
+    registerGoalExtension(this.api);
+  }
+
+  async emit(event: string, value: Record<string, unknown> = {}): Promise<unknown[]> {
+    const results: unknown[] = [];
+    for (const handler of this.handlers.get(event) ?? []) {
+      results.push(await handler(value, this.context));
+    }
+    return results;
+  }
+
+  async goal(args: string): Promise<void> {
+    const handler = this.commands.get('goal');
+    if (handler === undefined) throw new Error('/goal was not registered');
+    await handler(args, this.context);
+  }
+
+  async report(params: Record<string, unknown>): Promise<FakeToolResult> {
+    const tool = this.tools.get('mosaic_goal_report');
+    if (tool === undefined) throw new Error('mosaic_goal_report was not registered');
+    return await tool.execute('goal-report-1', params, undefined, undefined, this.context);
+  }
+}
+
+function latestGoalStateData(pi: FakePi): Record<string, unknown> {
+  for (let index = pi.entries.length - 1; index >= 0; index -= 1) {
+    const entry = pi.entries[index];
+    if (entry?.customType === 'mosaic-goal-state' && isRecord(entry.data)) return entry.data;
+  }
+  throw new Error('No persisted Mosaic goal state found');
+}
+
+function stateField(pi: FakePi, field: string): unknown {
+  return latestGoalStateData(pi)[field];
+}
+
+function activeGoalStatementFromContext(result: unknown): string {
+  if (!isRecord(result)) throw new Error('Context handler did not return an object');
+  const messages = result['messages'];
+  if (!Array.isArray(messages)) throw new Error('Context result did not include messages');
+  const goalMessage = messages.find(
+    (message: unknown): boolean =>
+      isRecord(message) && message['customType'] === 'mosaic-goal-context',
+  );
+  if (!isRecord(goalMessage) || typeof goalMessage['content'] !== 'string') {
+    throw new Error('Goal context message was not injected');
+  }
+  return goalMessage['content'];
+}
+
+afterEach(() => {
+  vi.useRealTimers();
+  vi.unstubAllEnvs();
+});
+
+describe('Mosaic Pi goal extension commands', () => {
+  it('shows help and handles controls safely when no goal exists', async () => {
+    const pi = new FakePi();
+
+    await pi.goal('');
+    expect(pi.notifications.at(-1)?.message).toContain('/goal set');
+    await pi.goal('status');
+    expect(pi.notifications.at(-1)?.message).toContain('No Mosaic goal is set');
+
+    for (const command of ['pause', 'resume', 'cancel']) {
+      await pi.goal(command);
+      expect(pi.notifications.at(-1)?.level).toBe('warning');
+    }
+    expect(pi.entries).toHaveLength(0);
+    expect(pi.sentMessages).toHaveLength(0);
+  });
+
+  it('sets, reports, pauses, resumes, and cancels a bounded goal', async () => {
+    const pi = new FakePi();
+
+    await pi.goal('set Deliver the local goal extension with tests');
+    expect(stateField(pi, 'phase')).toBe('active');
+    expect(stateField(pi, 'statement')).toBe('Deliver the local goal extension with tests');
+    expect(pi.sentMessages).toHaveLength(1);
+    expect(pi.sentMessages[0]?.options?.triggerTurn).toBe(true);
+
+    await pi.goal('status');
+    expect(pi.notifications.at(-1)?.message).toContain('Deliver the local goal extension');
+    expect(pi.notifications.at(-1)?.message).toContain('active');
+
+    await pi.goal('pause');
+    expect(stateField(pi, 'phase')).toBe('paused');
+    pi.sentMessages.length = 0;
+    await pi.emit('agent_settled');
+    expect(pi.sentMessages).toHaveLength(0);
+
+    await pi.goal('resume');
+    expect(stateField(pi, 'phase')).toBe('active');
+    expect(pi.sentMessages).toHaveLength(1);
+
+    await pi.goal('cancel');
+    expect(stateField(pi, 'phase')).toBe('cancelled');
+    pi.sentMessages.length = 0;
+    await pi.emit('agent_settled');
+    expect(pi.sentMessages).toHaveLength(0);
+  });
+
+  it('accepts /goal <statement> shorthand but refuses to replace an active goal', async () => {
+    const pi = new FakePi();
+
+    await pi.goal('First goal');
+    const firstGoalId = stateField(pi, 'goalId');
+    await pi.goal('set Second goal');
+
+    expect(stateField(pi, 'goalId')).toBe(firstGoalId);
+    expect(stateField(pi, 'statement')).toBe('First goal');
+    expect(pi.notifications.at(-1)?.level).toBe('warning');
+    expect(pi.notifications.at(-1)?.message).toContain('/goal cancel');
+  });
+
+  it('rejects invalid phase transitions, aborts busy work, and supports clear as cancel', async () => {
+    const pi = new FakePi();
+    await pi.goal('set Preserve transition safety');
+
+    await pi.goal('resume');
+    expect(pi.notifications.at(-1)?.message).toContain('cannot be resumed');
+    pi.idle = false;
+    await pi.goal('pause maintenance window');
+    expect(stateField(pi, 'stopReason')).toBe('maintenance window');
+    expect(pi.abortCount).toBe(1);
+    await pi.goal('pause');
+    expect(pi.notifications.at(-1)?.message).toContain('cannot be paused');
+    await pi.goal('clear');
+    expect(stateField(pi, 'phase')).toBe('cancelled');
+    expect(pi.abortCount).toBe(2);
+  });
+
+  it('rejects empty and oversized goal statements without starting a run', async () => {
+    const pi = new FakePi();
+
+    await pi.goal('set');
+    await pi.goal(`set ${'x'.repeat(8_001)}`);
+
+    expect(pi.entries).toHaveLength(0);
+    expect(pi.sentMessages).toHaveLength(0);
+    expect(pi.notifications.at(-1)?.level).toBe('warning');
+  });
+});
+
+describe('Mosaic Pi goal lifecycle', () => {
+  it('injects one fresh active contract before every model context', async () => {
+    const pi = new FakePi();
+    await pi.goal('set Keep the agent oriented');
+
+    const existingGoalContext = {
+      role: 'custom',
+      customType: 'mosaic-goal-context',
+      content: 'stale',
+    };
+    const existingContinuation = {
+      role: 'custom',
+      customType: 'mosaic-goal-continuation',
+      content: 'stale continuation',
+    };
+    const first = await pi.emit('context', {
+      messages: [existingGoalContext, existingContinuation],
+    });
+    const second = await pi.emit('context', { messages: [] });
+
+    expect(activeGoalStatementFromContext(first[0])).toContain('Keep the agent oriented');
+    expect(activeGoalStatementFromContext(first[0])).toContain('mosaic_goal_report');
+    expect(activeGoalStatementFromContext(first[0])).not.toContain('stale');
+    if (!isRecord(first[0]) || !Array.isArray(first[0]['messages'])) {
+      throw new Error('Expected filtered context messages');
+    }
+    expect(first[0]['messages']).toHaveLength(1);
+    expect(activeGoalStatementFromContext(second[0])).toContain('Keep the agent oriented');
+
+    await pi.goal('cancel');
+    expect(
+      await pi.emit('context', {
+        messages: [existingGoalContext, existingContinuation],
+      }),
+    ).toEqual([{ messages: [] }]);
+  });
+
+  it('lets an existing busy run adopt the goal and waits behind a pending message', async () => {
+    const busy = new FakePi();
+    busy.idle = false;
+    await busy.goal('set Join the current run safely');
+    expect(busy.sentMessages).toHaveLength(0);
+
+    busy.pending = true;
+    await busy.emit('agent_settled');
+    expect(busy.sentMessages).toHaveLength(0);
+    busy.pending = false;
+    busy.idle = true;
+    await busy.emit('agent_settled');
+    expect(busy.sentMessages).toHaveLength(1);
+  });
+
+  it('records every turn and continues once when an active run settles', async () => {
+    const pi = new FakePi();
+    await pi.goal('set Finish all acceptance criteria');
+    pi.sentMessages.length = 0;
+
+    await pi.emit('turn_end', { turnIndex: 0, message: {}, toolResults: [] });
+    expect(stateField(pi, 'turnCount')).toBe(1);
+    expect(stateField(pi, 'lastCheckSource')).toBe('turn');
+
+    await pi.emit('agent_settled');
+    await pi.emit('agent_settled');
+    expect(pi.sentMessages).toHaveLength(1);
+    expect(pi.sentMessages[0]?.message.content).toContain('Goal remains active');
+
+    await pi.emit('agent_start');
+    await pi.emit('agent_settled');
+    expect(pi.sentMessages).toHaveLength(2);
+  });
+
+  it('requires two consecutive evidence-bearing achievement reports', async () => {
+    const pi = new FakePi();
+    await pi.goal('set Prove the feature works');
+    pi.sentMessages.length = 0;
+
+    const first = await pi.report({
+      status: 'achieved',
+      summary: 'Focused tests pass',
+      evidence: ['pnpm test: 12 passed'],
+    });
+    expect(first.terminate).toBe(true);
+    expect(stateField(pi, 'phase')).toBe('verifying');
+    expect(stateField(pi, 'verificationPasses')).toBe(1);
+
+    await pi.emit('agent_settled');
+    expect(pi.sentMessages).toHaveLength(1);
+    expect(pi.sentMessages[0]?.message.content).toContain('verification pass');
+
+    await pi.emit('agent_start');
+    const second = await pi.report({
+      status: 'achieved',
+      summary: 'Independent recheck confirms completion',
+      evidence: ['rerun: 12 passed', 'framework path verified'],
+    });
+    expect(second.terminate).toBe(true);
+    expect(stateField(pi, 'phase')).toBe('achieved');
+    expect(stateField(pi, 'verificationPasses')).toBe(2);
+
+    pi.sentMessages.length = 0;
+    await pi.emit('agent_settled');
+    expect(pi.sentMessages).toHaveLength(0);
+  });
+
+  it('rejects malformed progress reports and reports submitted without an active goal', async () => {
+    const noGoal = new FakePi();
+    await expect(
+      noGoal.report({ status: 'continue', summary: 'work', evidence: [] }),
+    ).rejects.toThrow(/No active Mosaic goal/);
+
+    const pi = new FakePi();
+    await pi.goal('set Validate report boundaries');
+    const invalidReports: Record<string, unknown>[] = [
+      {},
+      { status: 'invalid', summary: 'work', evidence: [] },
+      { status: 'continue', evidence: [] },
+      { status: 'continue', summary: '   ', evidence: [] },
+      { status: 'continue', summary: 'x'.repeat(2_001), evidence: [] },
+      { status: 'continue', summary: 'work', evidence: 'not-an-array' },
+      { status: 'continue', summary: 'work', evidence: Array.from({ length: 21 }, () => 'x') },
+      { status: 'continue', summary: 'work', evidence: [4] },
+      { status: 'continue', summary: 'work', evidence: [''] },
+      { status: 'continue', summary: 'work', evidence: ['x'.repeat(1_001)] },
+      { status: 'continue', summary: 'work', evidence: [], nextStep: 4 },
+      { status: 'continue', summary: 'work', evidence: [], nextStep: '   ' },
+      { status: 'continue', summary: 'work', evidence: [], nextStep: 'x'.repeat(2_001) },
+    ];
+    for (const report of invalidReports) {
+      await expect(pi.report(report)).rejects.toThrow();
+    }
+    expect(stateField(pi, 'phase')).toBe('active');
+  });
+
+  it('rejects an achievement claim without evidence', async () => {
+    const pi = new FakePi();
+    await pi.goal('set Require evidence');
+
+    await expect(
+      pi.report({ status: 'achieved', summary: 'Trust me', evidence: [] }),
+    ).rejects.toThrow(/evidence/i);
+    expect(stateField(pi, 'phase')).toBe('active');
+  });
+
+  it('redacts credential-shaped goal and report text before persistence or display', async () => {
+    const githubToken = `ghp_${'a'.repeat(32)}`;
+    const anthropicKey = `sk-ant-api03-${'b'.repeat(40)}`;
+    const bearerToken = 'header.payload.signature-canary';
+    const databaseUrl = 'postgresql://mosaic:[email protected]/mosaic';
+    const password = 'password-canary';
+    const pi = new FakePi();
+
+    await pi.goal(`set Rotate ${githubToken} without retaining it`);
+    const context = await pi.emit('context', { messages: [] });
+    expect(activeGoalStatementFromContext(context[0])).not.toContain(githubToken);
+
+    const result = await pi.report({
+      status: 'achieved',
+      summary: `Validated ${anthropicKey}`,
+      evidence: [`Authorization: Bearer ${bearerToken}`, `DATABASE_URL=${databaseUrl}`],
+      nextStep: `password=${password}`,
+    });
+    await pi.goal('status');
+
+    const persisted = JSON.stringify(latestGoalStateData(pi));
+    const displayed = pi.notifications.at(-1)?.message ?? '';
+    const toolOutput = JSON.stringify(result);
+    for (const secret of [githubToken, anthropicKey, bearerToken, databaseUrl, password]) {
+      expect(persisted).not.toContain(secret);
+      expect(displayed).not.toContain(secret);
+      expect(toolOutput).not.toContain(secret);
+    }
+    expect(persisted).toContain('[REDACTED-SECRET]');
+  });
+
+  it('preserves ordinary typed fields that resemble sensitive assignment names', async () => {
+    const typedFields = 'token: string, password: boolean, secret: false';
+    const pi = new FakePi();
+
+    await pi.goal(`set Preserve TypeScript fields: ${typedFields}`);
+    await pi.report({
+      status: 'continue',
+      summary: `Schema still contains ${typedFields}`,
+      evidence: [`interface Config { ${typedFields} }`],
+      nextStep: `Keep ${typedFields} unchanged`,
+    });
+
+    expect(stateField(pi, 'statement')).toContain(typedFields);
+    expect(JSON.stringify(stateField(pi, 'lastReport'))).toContain(typedFields);
+    expect(JSON.stringify(latestGoalStateData(pi))).not.toContain('[REDACTED-SECRET]');
+  });
+
+  it('stops autonomous continuation when the max-turn limit is reached', async () => {
+    vi.stubEnv('MOSAIC_GOAL_MAX_TURNS', '2');
+    const pi = new FakePi();
+    await pi.goal('set Bound this run');
+    pi.sentMessages.length = 0;
+
+    await pi.emit('turn_end', { turnIndex: 0, message: {}, toolResults: [] });
+    await pi.emit('turn_end', { turnIndex: 1, message: {}, toolResults: [] });
+
+    expect(stateField(pi, 'phase')).toBe('exhausted');
+    expect(pi.abortCount).toBe(1);
+    await pi.emit('agent_settled');
+    expect(pi.sentMessages).toHaveLength(0);
+  });
+
+  it('resets the no-progress sequence when a continuation report changes', async () => {
+    const pi = new FakePi();
+    await pi.goal('set Track changing progress');
+
+    await pi.report({
+      status: 'continue',
+      summary: 'First checkpoint',
+      evidence: ['file A changed'],
+      nextStep: 'Run focused tests',
+    });
+    await pi.report({
+      status: 'continue',
+      summary: 'Second checkpoint',
+      evidence: ['focused tests passed'],
+      nextStep: 'Review the diff',
+    });
+
+    expect(stateField(pi, 'phase')).toBe('active');
+    expect(stateField(pi, 'noProgressReports')).toBe(1);
+    await pi.goal('status');
+    expect(pi.notifications.at(-1)?.message).toContain('Next step: Review the diff');
+    expect(pi.notifications.at(-1)?.message).toContain('focused tests passed');
+  });
+
+  it('stops after a bounded number of identical no-progress reports', async () => {
+    vi.stubEnv('MOSAIC_GOAL_MAX_NO_PROGRESS', '2');
+    const pi = new FakePi();
+    await pi.goal('set Detect stalled work');
+
+    const report = {
+      status: 'continue',
+      summary: 'No change yet',
+      evidence: ['same observation'],
+      nextStep: 'Try again',
+    };
+    await pi.report(report);
+    await pi.report(report);
+
+    expect(stateField(pi, 'phase')).toBe('exhausted');
+    expect(stateField(pi, 'noProgressReports')).toBe(2);
+    pi.sentMessages.length = 0;
+    await pi.emit('agent_settled');
+    expect(pi.sentMessages).toHaveLength(0);
+  });
+
+  it('rejects a goal report mixed with another tool result in the same turn', async () => {
+    const pi = new FakePi();
+    await pi.goal('set Require a sole final report');
+    await pi.report({
+      status: 'achieved',
+      summary: 'Premature mixed claim',
+      evidence: ['one observation'],
+    });
+
+    await pi.emit('turn_end', {
+      turnIndex: 0,
+      message: {},
+      toolResults: [{ toolName: 'mosaic_goal_report' }, { toolName: 'read' }],
+    });
+
+    expect(stateField(pi, 'phase')).toBe('active');
+    expect(stateField(pi, 'verificationPasses')).toBe(0);
+    expect(stateField(pi, 'lastCheckOutcome')).toBe('mixed-goal-report-rejected');
+    expect(pi.notifications.at(-1)?.level).toBe('warning');
+  });
+
+  it('marks blocked reports terminal until the operator resumes', async () => {
+    const pi = new FakePi();
+    await pi.goal('set Stop on a real blocker');
+
+    await pi.report({
+      status: 'blocked',
+      summary: 'Missing required access',
+      evidence: ['provider returned 403'],
+    });
+    expect(stateField(pi, 'phase')).toBe('blocked');
+
+    pi.sentMessages.length = 0;
+    await pi.emit('agent_settled');
+    expect(pi.sentMessages).toHaveLength(0);
+
+    await pi.goal('resume');
+    expect(stateField(pi, 'phase')).toBe('active');
+    expect(stateField(pi, 'turnCount')).toBe(0);
+    expect(pi.sentMessages).toHaveLength(1);
+  });
+});
+
+describe('Mosaic Pi goal compaction and restoration', () => {
+  it('resets provisional verification and defers manual-compaction continuation until idle', async () => {
+    vi.useFakeTimers();
+    const pi = new FakePi();
+    await pi.goal('set Survive compaction');
+    await pi.report({
+      status: 'achieved',
+      summary: 'Initial claim',
+      evidence: ['focused test passed'],
+    });
+    expect(stateField(pi, 'phase')).toBe('verifying');
+    pi.sentMessages.length = 0;
+
+    await pi.emit('session_compact', { reason: 'manual', willRetry: false });
+    expect(stateField(pi, 'phase')).toBe('active');
+    expect(stateField(pi, 'verificationPasses')).toBe(0);
+    expect(stateField(pi, 'compactionCount')).toBe(1);
+    expect(stateField(pi, 'lastCheckSource')).toBe('compact');
+    expect(pi.sentMessages).toHaveLength(0);
+
+    await vi.runAllTimersAsync();
+    expect(pi.sentMessages).toHaveLength(1);
+    expect(pi.sentMessages[0]?.message.content).toContain('compaction');
+  });
+
+  it('does not re-enter an active automatic compaction and relies on the settled backstop', async () => {
+    vi.useFakeTimers();
+    const pi = new FakePi();
+    await pi.goal('set Avoid compaction races');
+    pi.sentMessages.length = 0;
+    pi.idle = false;
+
+    await pi.emit('session_compact', { reason: 'threshold', willRetry: false });
+    await vi.runAllTimersAsync();
+    expect(pi.sentMessages).toHaveLength(0);
+
+    pi.idle = true;
+    await pi.emit('agent_settled');
+    expect(pi.sentMessages).toHaveLength(1);
+  });
+
+  it('restores branch-specific state on session start and tree navigation', async () => {
+    vi.useFakeTimers();
+    const source = new FakePi();
+    await source.goal('set Restore this exact branch goal');
+    const activeState = latestGoalStateData(source);
+
+    const restored = new FakePi([
+      { type: 'custom', customType: 'mosaic-goal-state', data: activeState },
+    ]);
+    await restored.emit('session_start', { reason: 'resume' });
+    expect(restored.statuses.get('mosaic-goal')).toContain('active');
+    const context = await restored.emit('context', { messages: [] });
+    expect(activeGoalStatementFromContext(context[0])).toContain('Restore this exact branch goal');
+
+    await restored.goal('pause');
+    const pausedState = latestGoalStateData(restored);
+    restored.branch = [{ type: 'custom', customType: 'mosaic-goal-state', data: pausedState }];
+    await restored.emit('session_tree', {});
+    await vi.runAllTimersAsync();
+    expect(stateField(restored, 'phase')).toBe('paused');
+    expect(restored.sentMessages).toHaveLength(0);
+  });
+
+  it('restores only fully valid persisted states and ignores malformed entries', async () => {
+    vi.useFakeTimers();
+    const source = new FakePi();
+    await source.goal('set Validate persisted branch state');
+    await source.report({
+      status: 'continue',
+      summary: 'Valid report',
+      evidence: ['valid evidence'],
+      nextStep: 'Continue validation',
+    });
+    const valid = latestGoalStateData(source);
+
+    const validRestore = new FakePi([
+      { type: 'custom', customType: 'mosaic-goal-state', data: valid },
+    ]);
+    await validRestore.emit('session_start', { reason: 'resume' });
+    expect(stateField(validRestore, 'statement')).toBe('Validate persisted branch state');
+    await validRestore.emit('session_shutdown', { reason: 'reload' });
+
+    const validReport = latestGoalStateData(source)['lastReport'];
+    if (!isRecord(validReport)) throw new Error('Expected a valid persisted report fixture');
+    const integerFields = [
+      'turnCount',
+      'reportCount',
+      'verificationPasses',
+      'requiredVerificationPasses',
+      'noProgressReports',
+      'maxTurns',
+      'maxNoProgressReports',
+      'compactionCount',
+    ];
+    const corruptions: Array<(state: Record<string, unknown>) => unknown> = [
+      (): unknown => null,
+      (state): unknown => ({ ...state, version: 99 }),
+      (state): unknown => ({ ...state, goalId: '' }),
+      (state): unknown => ({ ...state, statement: '' }),
+      (state): unknown => ({ ...state, statement: 'x'.repeat(8_001) }),
+      (state): unknown => ({ ...state, phase: 'unknown' }),
+      (state): unknown => ({ ...state, lastCheckSource: 'unknown' }),
+      (state): unknown => ({ ...state, startedAt: 4 }),
+      (state): unknown => ({ ...state, lastCheckAt: 4 }),
+      (state): unknown => ({ ...state, lastReport: null }),
+      (state): unknown => ({ ...state, lastProgressFingerprint: 4 }),
+      (state): unknown => ({ ...state, stopReason: 4 }),
+      ...integerFields.map((field: string) => (state: Record<string, unknown>): unknown => ({
+        ...state,
+        [field]: -1,
+      })),
+    ];
+
+    corruptions.push(
+      (state: Record<string, unknown>): unknown => ({ ...state, maxTurns: 501 }),
+      (state: Record<string, unknown>): unknown => ({ ...state, maxNoProgressReports: 101 }),
+      (state: Record<string, unknown>): unknown => ({ ...state, requiredVerificationPasses: 3 }),
+    );
+    const reportCorruptions: Array<Record<string, unknown>> = [
+      { ...validReport, status: 'bad' },
+      { ...validReport, summary: '' },
+      { ...validReport, evidence: 'bad' },
+      { ...validReport, evidence: [4] },
+      { ...validReport, fingerprint: '' },
+      { ...validReport, reportedAt: '' },
+      { ...validReport, nextStep: 4 },
+    ];
+    for (const corruptReport of reportCorruptions) {
+      corruptions.push((state: Record<string, unknown>): unknown => ({
+        ...state,
+        lastReport: corruptReport,
+      }));
+    }
+
+    for (const corrupt of corruptions) {
+      const candidate = corrupt(structuredClone(valid));
+      const restored = new FakePi([
+        { type: 'custom', customType: 'mosaic-goal-state', data: candidate },
+      ]);
+      await restored.emit('session_start', { reason: 'resume' });
+      expect(restored.statuses.get('mosaic-goal')).toBeUndefined();
+      expect(await restored.emit('context', { messages: [] })).toEqual([undefined]);
+    }
+
+    const failClosed = new FakePi([
+      { type: 'custom', customType: 'mosaic-goal-state', data: valid },
+      { type: 'custom', customType: 'mosaic-goal-state', data: { ...valid, version: 99 } },
+    ]);
+    await failClosed.emit('session_start', { reason: 'resume' });
+    expect(failClosed.statuses.get('mosaic-goal')).toBeUndefined();
+  });
+
+  it('fails closed instead of reusing credential-bearing legacy branch state', async () => {
+    const source = new FakePi();
+    await source.goal('set Build a valid restore fixture');
+    const cleanState = latestGoalStateData(source);
+    const legacyState = structuredClone(cleanState);
+    legacyState['statement'] = `Legacy secret ghp_${'z'.repeat(32)}`;
+
+    const restored = new FakePi([
+      { type: 'custom', customType: 'mosaic-goal-state', data: legacyState },
+      { type: 'custom', customType: 'mosaic-goal-state', data: cleanState },
+    ]);
+    await restored.emit('session_start', { reason: 'resume' });
+
+    expect(restored.statuses.get('mosaic-goal')).toBeUndefined();
+    expect(await restored.emit('context', { messages: [] })).toEqual([undefined]);
+    expect(restored.notifications.at(-1)?.level).toBe('warning');
+    expect(restored.notifications.at(-1)?.message).toContain('was not restored');
+    expect(restored.entries).toHaveLength(0);
+  });
+
+  it('schedules an active tree-restored goal and preserves terminal state through compaction', async () => {
+    vi.useFakeTimers();
+    const source = new FakePi();
+    await source.goal('set Restore active tree work');
+    const active = latestGoalStateData(source);
+
+    const restored = new FakePi();
+    restored.branch = [{ type: 'custom', customType: 'mosaic-goal-state', data: active }];
+    await restored.emit('session_tree', {});
+    await vi.runAllTimersAsync();
+    expect(restored.sentMessages).toHaveLength(1);
+    expect(restored.sentMessages[0]?.message.content).toContain('tree navigation');
+
+    await restored.goal('cancel');
+    await restored.emit('session_compact', { reason: 'manual', willRetry: false });
+    expect(stateField(restored, 'phase')).toBe('cancelled');
+    expect(stateField(restored, 'compactionCount')).toBe(1);
+  });
+
+  it('cancels deferred continuation when the session shuts down', async () => {
+    vi.useFakeTimers();
+    const pi = new FakePi();
+    await pi.goal('set Do not leak a stale timer');
+    pi.sentMessages.length = 0;
+
+    await pi.emit('session_compact', { reason: 'manual', willRetry: false });
+    await pi.emit('session_shutdown', { reason: 'reload' });
+    await vi.runAllTimersAsync();
+
+    expect(pi.sentMessages).toHaveLength(0);
+  });
+});