feat(fleet): add shared role semantics

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

packages/mosaic/src/fleet/persona-contract.spec.ts

@@ -77,12 +77,25 @@ describe('readPersonaContractBlock — launch-time persona injection (A3b)', ()
   });
 
   it('injects an override-only (user-added) persona with no baseline at all', () => {
-    seedOverride(home, 'reviewer', '# Reviewer\n\n(`class: reviewer`)\n\nCUSTOM-ROLE.\n');
-    const block = readPersonaContractBlock(home, 'reviewer');
-    expect(block).toContain('# Persona Contract (reviewer)');
+    seedOverride(home, 'mascot', '# Mascot\n\n(`class: mascot`)\n\nCUSTOM-ROLE.\n');
+    const block = readPersonaContractBlock(home, 'mascot');
+    expect(block).toContain('# Persona Contract (mascot)');
     expect(block).toContain('CUSTOM-ROLE');
   });
 
+  it('canonicalizes an approved alias before launch-time override lookup', () => {
+    seedBaseline(home, 'code', '# Code\n\n(`class: code`)\n\nCANONICAL-CODE.\n');
+    seedOverride(
+      home,
+      'implementer',
+      '# Legacy implementer\n\n(`class: implementer`)\n\nLEGACY-OVERRIDE.\n',
+    );
+    const block = readPersonaContractBlock(home, 'implementer');
+    expect(block).toContain('# Persona Contract (code)');
+    expect(block).toContain('CANONICAL-CODE');
+    expect(block).not.toContain('LEGACY-OVERRIDE');
+  });
+
   it('no-ops (empty string) when the class is undefined', () => {
     seedBaseline(home, 'coder', BASELINE_CODER);
     expect(readPersonaContractBlock(home, undefined)).toBe('');

packages/mosaic/src/fleet/roster-v2.spec.ts

@@ -1,11 +1,14 @@
-import { readFile } from 'node:fs/promises';
+import { chmod, mkdir, mkdtemp, readFile, rm, writeFile } from 'node:fs/promises';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
 import { fileURLToPath } from 'node:url';
-import { describe, expect, it } from 'vitest';
+import { afterEach, describe, expect, it } from 'vitest';
 import {
   ROSTER_V2_JSON_SCHEMA,
   RosterV2ValidationError,
   parseRosterV2,
   renderRosterV2Yaml,
+  validateRosterV2Semantics,
 } from './roster-v2.js';
 
 const validRoster = `
@@ -40,6 +43,133 @@ agents:
       yolo: true
 `;
 
+let semanticTmp: string | undefined;
+
+afterEach(async (): Promise<void> => {
+  if (semanticTmp) await rm(semanticTmp, { recursive: true, force: true });
+  semanticTmp = undefined;
+});
+
+async function semanticDirs(): Promise<{ rolesDir: string; overrideDir: string }> {
+  semanticTmp = await mkdtemp(join(tmpdir(), 'roster-v2-semantics-'));
+  const rolesDir = join(semanticTmp, 'roles');
+  const overrideDir = join(semanticTmp, 'roles.local');
+  await mkdir(rolesDir, { recursive: true });
+  await mkdir(overrideDir, { recursive: true });
+  for (const klass of [
+    'code',
+    'review',
+    'interaction',
+    'orchestrator',
+    'merge-gate',
+    'validator',
+    'team-leader',
+  ]) {
+    await writeFile(join(rolesDir, `${klass}.md`), `# ${klass}\n\n(\`class: ${klass}\`)\n`, 'utf8');
+  }
+  return { rolesDir, overrideDir };
+}
+
+function rosterWithClass(klass: string, toolPolicy = klass): string {
+  return validRoster
+    .replace('class: code', `class: ${klass}`)
+    .replace('tool_policy: code', `tool_policy: ${toolPolicy}`);
+}
+
+describe('roster v2 semantic validation', (): void => {
+  it.each([
+    ['implementer', 'code'],
+    ['reviewer', 'review'],
+    ['operator-interaction', 'interaction'],
+  ])(
+    'canonicalizes requested alias %s while retaining requested and canonical class',
+    async (requested: string, canonical: string) => {
+      const dirs = await semanticDirs();
+      const roster = parseRosterV2(rosterWithClass(requested, requested), 'yaml');
+      const validated = await validateRosterV2Semantics(roster, dirs);
+      expect(validated.agents[0]).toMatchObject({
+        requestedClass: requested,
+        canonicalClass: canonical,
+        canonicalToolPolicy: canonical,
+      });
+    },
+  );
+
+  it.each(['worker', 'analyst', 'canary'])(
+    'rejects %s when no genuine custom role exists',
+    async (klass: string) => {
+      const dirs = await semanticDirs();
+      await expect(
+        validateRosterV2Semantics(parseRosterV2(rosterWithClass(klass), 'yaml'), dirs),
+      ).rejects.toThrow(/unresolved|readable persona/i);
+    },
+  );
+
+  it('accepts a genuine custom roles.local class without protected authority', async () => {
+    const dirs = await semanticDirs();
+    await writeFile(join(dirs.overrideDir, 'worker.md'), '# worker\n\n(`class: worker`)\n', 'utf8');
+    const validated = await validateRosterV2Semantics(
+      parseRosterV2(rosterWithClass('worker'), 'yaml'),
+      dirs,
+    );
+    expect(validated.agents[0]?.authority).toMatchObject({
+      mayMerge: false,
+      mayOrchestrate: false,
+    });
+  });
+
+  it('rejects a LIBRARY-only class with no readable resolved persona', async () => {
+    const dirs = await semanticDirs();
+    await writeFile(
+      join(dirs.rolesDir, 'LIBRARY.md'),
+      '| Persona | Purpose |\n| --- | --- |\n| phantom | Missing |\n',
+      'utf8',
+    );
+    await expect(
+      validateRosterV2Semantics(parseRosterV2(rosterWithClass('phantom'), 'yaml'), dirs),
+    ).rejects.toThrow(/readable persona/i);
+  });
+
+  it('rejects an unreadable resolved persona', async () => {
+    const dirs = await semanticDirs();
+    const file = join(dirs.overrideDir, 'worker.md');
+    await writeFile(file, '# worker\n\n(`class: worker`)\n', 'utf8');
+    await chmod(file, 0o000);
+    try {
+      await expect(
+        validateRosterV2Semantics(parseRosterV2(rosterWithClass('worker'), 'yaml'), dirs),
+      ).rejects.toThrow(/readable persona/i);
+    } finally {
+      await chmod(file, 0o600);
+    }
+  });
+
+  it.each([
+    ['merge-gate', 'code'],
+    ['validator', 'merge-gate'],
+    ['orchestrator', 'interaction'],
+    ['team-leader', 'orchestrator'],
+    ['interaction', 'orchestrator'],
+    ['code', 'merge-gate'],
+    ['worker', 'validator'],
+  ])(
+    'denies protected class/tool-policy mismatch %s with %s',
+    async (klass: string, toolPolicy: string) => {
+      const dirs = await semanticDirs();
+      if (klass === 'worker') {
+        await writeFile(
+          join(dirs.overrideDir, 'worker.md'),
+          '# worker\n\n(`class: worker`)\n',
+          'utf8',
+        );
+      }
+      await expect(
+        validateRosterV2Semantics(parseRosterV2(rosterWithClass(klass, toolPolicy), 'yaml'), dirs),
+      ).rejects.toThrow(/tool policy.*must match|mismatch/i);
+    },
+  );
+});
+
 describe('roster v2 structural compiler', (): void => {
   it('parses YAML into a normalized typed model and renders canonical YAML', (): void => {
     const roster = parseRosterV2(validRoster, 'yaml');

packages/mosaic/src/fleet/roster-v2.ts

@@ -1,4 +1,15 @@
 import YAML from 'yaml';
+import {
+  authorityForCanonicalClass,
+  canonicalizeRoleClass,
+  defaultOverrideDir,
+  defaultRolesDir,
+  extractClassesFromDir,
+  resolvePersonaFrom,
+  type PersonaDirs,
+  type PersonaResolution,
+  type RoleAuthority,
+} from '../commands/fleet-personas.js';
 
 export const ROSTER_V2_SUPPORTED_RUNTIMES = ['claude', 'codex', 'opencode', 'pi'] as const;
 export const ROSTER_V2_REASONING_LEVELS = ['low', 'medium', 'high'] as const;
@@ -58,6 +69,80 @@ export interface FleetRosterV2 {
   readonly agents: readonly FleetRosterV2Agent[];
 }
 
+export interface SemanticallyValidatedRosterV2Agent extends FleetRosterV2Agent {
+  readonly requestedClass: string;
+  readonly canonicalClass: string;
+  readonly canonicalToolPolicy: string;
+  readonly persona: PersonaResolution;
+  readonly authority: RoleAuthority;
+}
+
+export interface SemanticallyValidatedRosterV2 extends Omit<FleetRosterV2, 'agents'> {
+  readonly agents: readonly SemanticallyValidatedRosterV2Agent[];
+}
+
+const PROTECTED_TOOL_POLICY_CLASSES = new Set([
+  'merge-gate',
+  'validator',
+  'orchestrator',
+  'team-leader',
+  'interaction',
+]);
+
+/**
+ * Validate filesystem-backed roster semantics after synchronous structural parsing.
+ * Directory scans are batched once and every class must resolve to readable content.
+ */
+export async function validateRosterV2Semantics(
+  roster: FleetRosterV2,
+  opts: PersonaDirs = {},
+): Promise<SemanticallyValidatedRosterV2> {
+  const rolesDir = opts.rolesDir ?? defaultRolesDir(opts.mosaicHome);
+  const overrideDir = opts.overrideDir ?? defaultOverrideDir(opts.mosaicHome);
+  const [base, over] = await Promise.all([
+    extractClassesFromDir(rolesDir),
+    extractClassesFromDir(overrideDir),
+  ]);
+
+  const agents: SemanticallyValidatedRosterV2Agent[] = [];
+  for (const agent of roster.agents) {
+    const requestedClass = agent.className;
+    const { canonicalClass } = canonicalizeRoleClass(requestedClass);
+    const canonicalToolPolicy = canonicalizeRoleClass(agent.toolPolicy).canonicalClass;
+    const persona = await resolvePersonaFrom(requestedClass, {
+      rolesDir,
+      overrideDir,
+      base,
+      over,
+    });
+    if (!persona || persona.content.trim() === '') {
+      throw new RosterV2ValidationError(
+        `Roster v2 agent "${agent.name}" class "${requestedClass}" does not resolve to a readable persona.`,
+      );
+    }
+    if (
+      (PROTECTED_TOOL_POLICY_CLASSES.has(canonicalClass) ||
+        PROTECTED_TOOL_POLICY_CLASSES.has(canonicalToolPolicy)) &&
+      canonicalToolPolicy !== canonicalClass
+    ) {
+      throw new RosterV2ValidationError(
+        `Roster v2 agent "${agent.name}" protected class "${canonicalClass}" tool policy must match its canonical class; received "${agent.toolPolicy}".`,
+      );
+    }
+    agents.push(
+      Object.freeze({
+        ...agent,
+        requestedClass,
+        canonicalClass,
+        canonicalToolPolicy,
+        persona,
+        authority: authorityForCanonicalClass(canonicalClass),
+      }),
+    );
+  }
+  return Object.freeze({ ...roster, agents: Object.freeze(agents) });
+}
+
 export class RosterV2ValidationError extends Error {
   constructor(message: string) {
     super(message);