feat(#462): add federation get verb (#683)

FED-M3-06 get verb. Trust boundary mirrors M3-05 AND-intersect (note returned only when owned by subject AND on an authorized mission). Reviewed (review-of-record APPROVE, head 80a259b2) + green PR-event CI 1620.

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

apps/gateway/src/federation/federation.module.ts

@@ -5,6 +5,8 @@ import { EnrollmentController } from './enrollment.controller.js';
 import { EnrollmentService } from './enrollment.service.js';
 import { FederationController } from './federation.controller.js';
 import { CapabilitiesController } from './server/verbs/capabilities.controller.js';
+import { GetController } from './server/verbs/get.controller.js';
+import { FederationGetQueryService } from './server/verbs/get-query.service.js';
 import { GrantsService } from './grants.service.js';
 import { FederationClientService, QuerySourceService } from './client/index.js';
 import { FederationAuthGuard, FederationScopeService } from './server/index.js';
@@ -12,7 +14,13 @@ import { ListController } from './server/verbs/list.controller.js';
 import { FederationListQueryService } from './server/verbs/list-query.service.js';
 
 @Module({
-  controllers: [EnrollmentController, FederationController, CapabilitiesController, ListController],
+  controllers: [
+    EnrollmentController,
+    FederationController,
+    CapabilitiesController,
+    ListController,
+    GetController,
+  ],
   providers: [
     AdminGuard,
     CaService,
@@ -23,6 +31,7 @@ import { FederationListQueryService } from './server/verbs/list-query.service.js
     FederationAuthGuard,
     FederationScopeService,
     FederationListQueryService,
+    FederationGetQueryService,
   ],
   exports: [
     CaService,
@@ -33,6 +42,7 @@ import { FederationListQueryService } from './server/verbs/list-query.service.js
     FederationAuthGuard,
     FederationScopeService,
     FederationListQueryService,
+    FederationGetQueryService,
   ],
 })
 export class FederationModule {}

apps/gateway/src/federation/server/verbs/__tests__/get-query.service.spec.ts

@@ -0,0 +1,348 @@
+import { afterAll, beforeAll, describe, expect, it, vi } from 'vitest';
+import {
+  createPgliteDb,
+  missionTasks,
+  missions,
+  projects,
+  runPgliteMigrations,
+  teams,
+  users,
+  type Db,
+  type DbHandle,
+} from '@mosaicstack/db';
+import type { FederationScopeQueryFilter } from '../../scope.service.js';
+import { FederationGetQueryService } from '../get-query.service.js';
+
+const CREDENTIAL_FILTER: FederationScopeQueryFilter = {
+  resource: 'credentials',
+  subjectUserId: 'user-1',
+  includePersonal: true,
+  teamIds: [],
+  limit: 1,
+  maxRowsPerQuery: 25,
+};
+
+const SUBJECT_USER_ID = 'fed-m3-06-subject';
+const OTHER_USER_ID = 'fed-m3-06-other';
+const TEAM_ID = '06000000-0000-4000-8000-000000000001';
+const UNAUTHORIZED_TEAM_ID = '06000000-0000-4000-8000-000000000002';
+const PERSONAL_PROJECT_ID = '06000000-0000-4000-8000-000000000101';
+const TEAM_PROJECT_ID = '06000000-0000-4000-8000-000000000102';
+const UNAUTHORIZED_PROJECT_ID = '06000000-0000-4000-8000-000000000103';
+const PERSONAL_MISSION_ID = '06000000-0000-4000-8000-000000000201';
+const TEAM_MISSION_ID = '06000000-0000-4000-8000-000000000202';
+const UNAUTHORIZED_MISSION_ID = '06000000-0000-4000-8000-000000000203';
+const SUBJECT_TEAM_NOTE_ID = '06000000-0000-4000-8000-000000000301';
+const OTHER_TEAM_NOTE_ID = '06000000-0000-4000-8000-000000000302';
+const SUBJECT_PERSONAL_NOTE_ID = '06000000-0000-4000-8000-000000000303';
+const SUBJECT_UNAUTHORIZED_NOTE_ID = '06000000-0000-4000-8000-000000000304';
+
+let dbHandle: DbHandle | undefined;
+
+function makeService() {
+  return new FederationGetQueryService({} as Db);
+}
+
+function makeDbService() {
+  if (!dbHandle) {
+    throw new Error('test DB not initialized');
+  }
+  return new FederationGetQueryService(dbHandle.db);
+}
+
+async function seedNotesFixture() {
+  if (!dbHandle) {
+    throw new Error('test DB not initialized');
+  }
+
+  await dbHandle.db.insert(users).values([
+    {
+      id: SUBJECT_USER_ID,
+      name: 'Federation Subject',
+      email: `${SUBJECT_USER_ID}@example.test`,
+      emailVerified: false,
+    },
+    {
+      id: OTHER_USER_ID,
+      name: 'Federation Other',
+      email: `${OTHER_USER_ID}@example.test`,
+      emailVerified: false,
+    },
+  ]);
+
+  await dbHandle.db.insert(teams).values([
+    {
+      id: TEAM_ID,
+      name: 'FED-M3-06 Team',
+      slug: 'fed-m3-06-team',
+      ownerId: SUBJECT_USER_ID,
+      managerId: SUBJECT_USER_ID,
+    },
+    {
+      id: UNAUTHORIZED_TEAM_ID,
+      name: 'FED-M3-06 Unauthorized Team',
+      slug: 'fed-m3-06-unauthorized-team',
+      ownerId: OTHER_USER_ID,
+      managerId: OTHER_USER_ID,
+    },
+  ]);
+
+  await dbHandle.db.insert(projects).values([
+    {
+      id: PERSONAL_PROJECT_ID,
+      name: 'FED-M3-06 Personal Project',
+      ownerId: SUBJECT_USER_ID,
+      ownerType: 'user',
+    },
+    {
+      id: TEAM_PROJECT_ID,
+      name: 'FED-M3-06 Team Project',
+      teamId: TEAM_ID,
+      ownerType: 'team',
+    },
+    {
+      id: UNAUTHORIZED_PROJECT_ID,
+      name: 'FED-M3-06 Unauthorized Project',
+      teamId: UNAUTHORIZED_TEAM_ID,
+      ownerType: 'team',
+    },
+  ]);
+
+  await dbHandle.db.insert(missions).values([
+    {
+      id: PERSONAL_MISSION_ID,
+      name: 'FED-M3-06 Personal Mission',
+      projectId: PERSONAL_PROJECT_ID,
+      userId: SUBJECT_USER_ID,
+    },
+    {
+      id: TEAM_MISSION_ID,
+      name: 'FED-M3-06 Team Mission',
+      projectId: TEAM_PROJECT_ID,
+      userId: SUBJECT_USER_ID,
+    },
+    {
+      id: UNAUTHORIZED_MISSION_ID,
+      name: 'FED-M3-06 Unauthorized Mission',
+      projectId: UNAUTHORIZED_PROJECT_ID,
+      userId: SUBJECT_USER_ID,
+    },
+  ]);
+
+  await dbHandle.db.insert(missionTasks).values([
+    {
+      id: SUBJECT_TEAM_NOTE_ID,
+      missionId: TEAM_MISSION_ID,
+      userId: SUBJECT_USER_ID,
+      notes: 'subject note on team mission',
+      createdAt: new Date('2026-06-24T03:00:00.000Z'),
+      updatedAt: new Date('2026-06-24T03:00:00.000Z'),
+    },
+    {
+      id: OTHER_TEAM_NOTE_ID,
+      missionId: TEAM_MISSION_ID,
+      userId: OTHER_USER_ID,
+      notes: 'other user note on team mission',
+      createdAt: new Date('2026-06-24T02:00:00.000Z'),
+      updatedAt: new Date('2026-06-24T02:00:00.000Z'),
+    },
+    {
+      id: SUBJECT_PERSONAL_NOTE_ID,
+      missionId: PERSONAL_MISSION_ID,
+      userId: SUBJECT_USER_ID,
+      notes: 'subject note on personal mission',
+      createdAt: new Date('2026-06-24T01:00:00.000Z'),
+      updatedAt: new Date('2026-06-24T01:00:00.000Z'),
+    },
+    {
+      id: SUBJECT_UNAUTHORIZED_NOTE_ID,
+      missionId: UNAUTHORIZED_MISSION_ID,
+      userId: SUBJECT_USER_ID,
+      notes: 'subject note outside grant-visible missions',
+      createdAt: new Date('2026-06-24T04:00:00.000Z'),
+      updatedAt: new Date('2026-06-24T04:00:00.000Z'),
+    },
+  ]);
+}
+
+describe('FederationGetQueryService', () => {
+  beforeAll(async () => {
+    dbHandle = createPgliteDb(`memory://fed-m3-06-get-${Date.now()}`);
+    await runPgliteMigrations(dbHandle);
+    await seedNotesFixture();
+  });
+
+  afterAll(async () => {
+    await dbHandle?.close();
+    dbHandle = undefined;
+  });
+
+  it('denies sensitive resources in native RBAC for M3 get reads', async () => {
+    const service = makeService();
+
+    await expect(
+      service.evaluateReadAccess({
+        grantId: 'grant-1',
+        peerId: 'peer-1',
+        subjectUserId: 'user-1',
+        resource: 'credentials',
+      }),
+    ).resolves.toMatchObject({
+      allowed: false,
+      reason: 'credentials federation get access is not implemented in M3',
+    });
+  });
+
+  it('allows personal memory reads without requiring team lookup', async () => {
+    const service = makeService();
+
+    await expect(
+      service.evaluateReadAccess({
+        grantId: 'grant-1',
+        peerId: 'peer-1',
+        subjectUserId: 'user-1',
+        resource: 'memory',
+      }),
+    ).resolves.toEqual({
+      allowed: true,
+      access: { includePersonal: true, teamIds: [] },
+    });
+  });
+
+  it('uses subject team membership as the native RBAC upper bound for task and note reads', async () => {
+    const service = makeService();
+    const listSubjectTeamIds = vi.fn().mockResolvedValue(['team-1', 'team-2']);
+    (
+      service as unknown as {
+        listSubjectTeamIds: (subjectUserId: string) => Promise<string[]>;
+      }
+    ).listSubjectTeamIds = listSubjectTeamIds;
+
+    await expect(
+      service.evaluateReadAccess({
+        grantId: 'grant-1',
+        peerId: 'peer-1',
+        subjectUserId: 'user-1',
+        resource: 'tasks',
+      }),
+    ).resolves.toEqual({
+      allowed: true,
+      access: { includePersonal: true, teamIds: ['team-1', 'team-2'] },
+    });
+    expect(listSubjectTeamIds).toHaveBeenCalledWith('user-1');
+  });
+
+  it('does not query storage for sensitive get resources even if scope allowed them', async () => {
+    const service = makeService();
+
+    await expect(service.get({ filter: CREDENTIAL_FILTER, id: 'cred-1' })).resolves.toEqual({
+      status: 'denied',
+      reason: 'credentials federation get is not implemented',
+    });
+  });
+
+  it('fails closed for unsupported resources instead of returning undefined', async () => {
+    const service = makeService();
+
+    await expect(
+      service.get({
+        filter: {
+          ...CREDENTIAL_FILTER,
+          resource: 'unknown-resource' as FederationScopeQueryFilter['resource'],
+        },
+        id: 'row-1',
+      }),
+    ).resolves.toEqual({
+      status: 'denied',
+      reason: 'Unsupported federation get resource: unknown-resource',
+    });
+  });
+
+  it('does not leak another user mission task note through team-scoped get reads', async () => {
+    const service = makeDbService();
+
+    await expect(
+      service.get({
+        filter: {
+          resource: 'notes',
+          subjectUserId: SUBJECT_USER_ID,
+          includePersonal: false,
+          teamIds: [TEAM_ID],
+          limit: 1,
+          maxRowsPerQuery: 10,
+        },
+        id: OTHER_TEAM_NOTE_ID,
+      }),
+    ).resolves.toEqual({
+      status: 'denied',
+      reason: 'Note is outside the federated scope',
+    });
+  });
+
+  it('does not return subject notes from missions outside the grant-visible project set', async () => {
+    const service = makeDbService();
+
+    await expect(
+      service.get({
+        filter: {
+          resource: 'notes',
+          subjectUserId: SUBJECT_USER_ID,
+          includePersonal: true,
+          teamIds: [TEAM_ID],
+          limit: 1,
+          maxRowsPerQuery: 10,
+        },
+        id: SUBJECT_UNAUTHORIZED_NOTE_ID,
+      }),
+    ).resolves.toEqual({
+      status: 'denied',
+      reason: 'Note is outside the federated scope',
+    });
+  });
+
+  it('returns a subject note only when subject ownership and authorized mission intersect', async () => {
+    const service = makeDbService();
+
+    await expect(
+      service.get({
+        filter: {
+          resource: 'notes',
+          subjectUserId: SUBJECT_USER_ID,
+          includePersonal: false,
+          teamIds: [TEAM_ID],
+          limit: 1,
+          maxRowsPerQuery: 10,
+        },
+        id: SUBJECT_TEAM_NOTE_ID,
+      }),
+    ).resolves.toMatchObject({
+      status: 'found',
+      item: {
+        id: SUBJECT_TEAM_NOTE_ID,
+        missionId: TEAM_MISSION_ID,
+        content: 'subject note on team mission',
+      },
+    });
+  });
+
+  it('does not return subject personal notes when includePersonal is false', async () => {
+    const service = makeDbService();
+
+    await expect(
+      service.get({
+        filter: {
+          resource: 'notes',
+          subjectUserId: SUBJECT_USER_ID,
+          includePersonal: false,
+          teamIds: [TEAM_ID],
+          limit: 1,
+          maxRowsPerQuery: 10,
+        },
+        id: SUBJECT_PERSONAL_NOTE_ID,
+      }),
+    ).resolves.toEqual({
+      status: 'denied',
+      reason: 'Note is outside the federated scope',
+    });
+  });
+});

apps/gateway/src/federation/server/verbs/__tests__/get.controller.spec.ts

@@ -0,0 +1,207 @@
+import 'reflect-metadata';
+import { RequestMethod } from '@nestjs/common';
+import type { FastifyRequest } from 'fastify';
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import { FederationAuthGuard } from '../../federation-auth.guard.js';
+import type {
+  FederationScopeEvaluationResult,
+  FederationScopeQueryFilter,
+} from '../../scope.service.js';
+import { GetController } from '../get.controller.js';
+import type { FederationGetQueryResult } from '../get-query.service.js';
+
+const FEDERATION_CONTEXT = {
+  grantId: 'grant-1',
+  peerId: 'peer-1',
+  subjectUserId: 'user-1',
+  scope: { resources: ['tasks'], max_rows_per_query: 25 },
+};
+
+const TASK_FILTER: FederationScopeQueryFilter = {
+  resource: 'tasks',
+  subjectUserId: 'user-1',
+  includePersonal: true,
+  teamIds: ['team-1'],
+  limit: 1,
+  maxRowsPerQuery: 25,
+};
+
+function makeRequest(): FastifyRequest {
+  return { federationContext: FEDERATION_CONTEXT } as unknown as FastifyRequest;
+}
+
+function allowedScope(
+  filter: FederationScopeQueryFilter = TASK_FILTER,
+): FederationScopeEvaluationResult {
+  return { allowed: true, filter };
+}
+
+function makeController(opts?: {
+  scopeResult?: FederationScopeEvaluationResult;
+  queryResult?: FederationGetQueryResult;
+}) {
+  const scope = {
+    evaluateAccess: vi.fn().mockResolvedValue(opts?.scopeResult ?? allowedScope()),
+  };
+  const query = {
+    evaluateReadAccess: vi.fn(),
+    get: vi.fn().mockResolvedValue(
+      opts?.queryResult ?? {
+        status: 'found',
+        item: {
+          id: 'task-1',
+          title: 'Federated task',
+          createdAt: new Date('2026-06-24T00:00:00.000Z'),
+        },
+      },
+    ),
+  };
+
+  return {
+    controller: new GetController(scope as never, query as never),
+    scope,
+    query,
+  };
+}
+
+describe('GetController', () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  it('declares POST /api/federation/v1/get/:resource/:id protected only by FederationAuthGuard', () => {
+    expect(Reflect.getMetadata('path', GetController)).toBe('api/federation/v1/get');
+    expect(Reflect.getMetadata('path', GetController.prototype.get)).toBe(':resource/:id');
+    expect(Reflect.getMetadata('method', GetController.prototype.get)).toBe(RequestMethod.POST);
+    expect(Reflect.getMetadata('__guards__', GetController)).toEqual([FederationAuthGuard]);
+  });
+
+  it('runs AuthGuard context through ScopeService and returns one local-source tagged row', async () => {
+    const { controller, scope, query } = makeController();
+
+    const response = await controller.get('tasks', 'task-1', makeRequest());
+
+    expect(scope.evaluateAccess).toHaveBeenCalledWith({
+      context: FEDERATION_CONTEXT,
+      resource: 'tasks',
+      requestedLimit: 1,
+      nativeRbac: query,
+    });
+    expect(query.get).toHaveBeenCalledWith({ filter: TASK_FILTER, id: 'task-1' });
+    expect(response).toEqual({
+      item: {
+        id: 'task-1',
+        title: 'Federated task',
+        createdAt: new Date('2026-06-24T00:00:00.000Z'),
+        _source: 'local',
+      },
+    });
+  });
+
+  it('returns a federation error envelope when auth guard context is missing', async () => {
+    const { controller, scope, query } = makeController();
+
+    await expect(
+      controller.get('tasks', 'task-1', {} as unknown as FastifyRequest),
+    ).rejects.toMatchObject({
+      response: {
+        error: {
+          code: 'unauthorized',
+          message: 'Federation context missing',
+        },
+      },
+      status: 401,
+    });
+    expect(scope.evaluateAccess).not.toHaveBeenCalled();
+    expect(query.get).not.toHaveBeenCalled();
+  });
+
+  it('returns a federation error envelope when scope evaluation denies access', async () => {
+    const { controller, query } = makeController({
+      scopeResult: {
+        allowed: false,
+        deny: {
+          code: 'resource_excluded',
+          stage: 'resource_exclusion',
+          statusCode: 403,
+          message: 'Requested federation resource is explicitly excluded by grant scope',
+          grantId: 'grant-1',
+          peerId: 'peer-1',
+          subjectUserId: 'user-1',
+          resource: 'credentials',
+        },
+      },
+    });
+
+    await expect(controller.get('credentials', 'cred-1', makeRequest())).rejects.toMatchObject({
+      response: {
+        error: {
+          code: 'scope_violation',
+          message: 'Requested federation resource is explicitly excluded by grant scope',
+        },
+      },
+      status: 403,
+    });
+    expect(query.get).not.toHaveBeenCalled();
+  });
+
+  it('returns 404 when the scoped query layer cannot find the resource id', async () => {
+    const { controller } = makeController({ queryResult: { status: 'not_found' } });
+
+    await expect(controller.get('tasks', 'missing-task', makeRequest())).rejects.toMatchObject({
+      response: { error: { code: 'not_found' } },
+      status: 404,
+    });
+  });
+
+  it('returns 403 when the resource exists outside the RBAC/scope intersection', async () => {
+    const { controller } = makeController({
+      queryResult: { status: 'denied', reason: 'Task is outside the federated scope' },
+    });
+
+    await expect(controller.get('tasks', 'task-2', makeRequest())).rejects.toMatchObject({
+      response: {
+        error: {
+          code: 'scope_violation',
+          message: 'Task is outside the federated scope',
+        },
+      },
+      status: 403,
+    });
+  });
+
+  it('fails closed when the query layer denies an unsupported resource', async () => {
+    const unsupportedFilter: FederationScopeQueryFilter = {
+      ...TASK_FILTER,
+      resource: 'unknown-resource' as FederationScopeQueryFilter['resource'],
+    };
+    const { controller } = makeController({
+      scopeResult: allowedScope(unsupportedFilter),
+      queryResult: {
+        status: 'denied',
+        reason: 'Unsupported federation get resource: unknown-resource',
+      },
+    });
+
+    await expect(controller.get('unknown-resource', 'row-1', makeRequest())).rejects.toMatchObject({
+      response: {
+        error: {
+          code: 'scope_violation',
+          message: 'Unsupported federation get resource: unknown-resource',
+        },
+      },
+      status: 403,
+    });
+  });
+
+  it('rejects empty ids before evaluating scope', async () => {
+    const { controller, scope, query } = makeController();
+
+    await expect(controller.get('tasks', '   ', makeRequest())).rejects.toMatchObject({
+      response: { error: { code: 'invalid_request' } },
+      status: 400,
+    });
+    expect(scope.evaluateAccess).not.toHaveBeenCalled();
+    expect(query.get).not.toHaveBeenCalled();
+  });
+});

apps/gateway/src/federation/server/verbs/get-query.service.ts

@@ -0,0 +1,311 @@
+/**
+ * Federation get query layer (FED-M3-06).
+ *
+ * Read-only DB adapter used by GetController after FederationAuthGuard and
+ * FederationScopeService have established the subject user, allowed resource,
+ * native-RBAC intersection, and row cap. Audit writes are intentionally
+ * deferred to M4.
+ */
+
+import { Inject, Injectable } from '@nestjs/common';
+import {
+  and,
+  eq,
+  inArray,
+  insights,
+  or,
+  missionTasks,
+  missions,
+  preferences,
+  projects,
+  tasks,
+  teamMembers,
+  type Db,
+} from '@mosaicstack/db';
+import { DB } from '../../../database/database.module.js';
+import type {
+  FederationNativeRbacEvaluator,
+  FederationNativeRbacRequest,
+  FederationNativeRbacResult,
+  FederationScopeQueryFilter,
+} from '../scope.service.js';
+
+export interface FederationGetQueryRequest {
+  readonly filter: FederationScopeQueryFilter;
+  readonly id: string;
+}
+
+export interface FederationGetQueryFoundResult<T extends object = Record<string, unknown>> {
+  readonly status: 'found';
+  readonly item: T;
+}
+
+export interface FederationGetQueryNotFoundResult {
+  readonly status: 'not_found';
+}
+
+export interface FederationGetQueryDeniedResult {
+  readonly status: 'denied';
+  readonly reason: string;
+}
+
+export type FederationGetQueryResult<T extends object = Record<string, unknown>> =
+  | FederationGetQueryFoundResult<T>
+  | FederationGetQueryNotFoundResult
+  | FederationGetQueryDeniedResult;
+
+type RowObject = Record<string, unknown>;
+
+function firstRow<T>(rows: T[]): T | undefined {
+  return rows[0];
+}
+
+function rowBelongsToAccessibleProjectOrMission(
+  row: { projectId?: string | null; missionId?: string | null },
+  projectIds: readonly string[],
+  missionIds: readonly string[],
+): boolean {
+  return (
+    (typeof row.projectId === 'string' && projectIds.includes(row.projectId)) ||
+    (typeof row.missionId === 'string' && missionIds.includes(row.missionId))
+  );
+}
+
+@Injectable()
+export class FederationGetQueryService implements FederationNativeRbacEvaluator {
+  constructor(@Inject(DB) private readonly db: Db) {}
+
+  async evaluateReadAccess(
+    request: FederationNativeRbacRequest,
+  ): Promise<FederationNativeRbacResult> {
+    if (request.resource === 'credentials' || request.resource === 'api_keys') {
+      return {
+        allowed: false,
+        reason: `${request.resource} federation get access is not implemented in M3`,
+        details: { resource: request.resource },
+      };
+    }
+
+    if (request.resource === 'memory') {
+      return { allowed: true, access: { includePersonal: true, teamIds: [] } };
+    }
+
+    const teamIds = await this.listSubjectTeamIds(request.subjectUserId);
+    return { allowed: true, access: { includePersonal: true, teamIds } };
+  }
+
+  async get<T extends RowObject = RowObject>(
+    request: FederationGetQueryRequest,
+  ): Promise<FederationGetQueryResult<T>> {
+    return this.getByResource(request.filter, request.id) as Promise<FederationGetQueryResult<T>>;
+  }
+
+  private async getByResource(
+    filter: FederationScopeQueryFilter,
+    id: string,
+  ): Promise<FederationGetQueryResult> {
+    switch (filter.resource) {
+      case 'tasks':
+        return this.getTask(filter, id);
+      case 'notes':
+        return this.getNote(filter, id);
+      case 'memory':
+        return this.getMemory(filter, id);
+      case 'credentials':
+      case 'api_keys':
+        return { status: 'denied', reason: `${filter.resource} federation get is not implemented` };
+      default:
+        return {
+          status: 'denied',
+          reason: `Unsupported federation get resource: ${String(filter.resource)}`,
+        };
+    }
+  }
+
+  private async listSubjectTeamIds(subjectUserId: string): Promise<string[]> {
+    const rows = await this.db
+      .select({ teamId: teamMembers.teamId })
+      .from(teamMembers)
+      .where(eq(teamMembers.userId, subjectUserId));
+
+    return rows.map((row) => row.teamId);
+  }
+
+  private async listAccessibleProjectIds(filter: FederationScopeQueryFilter): Promise<string[]> {
+    const clauses = [];
+    if (filter.includePersonal) {
+      clauses.push(and(eq(projects.ownerType, 'user'), eq(projects.ownerId, filter.subjectUserId)));
+    }
+    if (filter.teamIds.length > 0) {
+      // Project team ownership follows TeamsService.canAccessProject: team-owned
+      // rows are authorized through projects.teamId, while ownerId remains the
+      // user who created/bootstrapped the project.
+      clauses.push(
+        and(eq(projects.ownerType, 'team'), inArray(projects.teamId, [...filter.teamIds])),
+      );
+    }
+
+    if (clauses.length === 0) {
+      return [];
+    }
+
+    const rows = await this.db
+      .select({ id: projects.id })
+      .from(projects)
+      .where(clauses.length === 1 ? clauses[0] : or(...clauses));
+
+    return rows.map((row) => row.id);
+  }
+
+  private async listMissionIds(projectIds: readonly string[]): Promise<string[]> {
+    if (projectIds.length === 0) {
+      return [];
+    }
+
+    const rows = await this.db
+      .select({ id: missions.id })
+      .from(missions)
+      .where(inArray(missions.projectId, [...projectIds]));
+
+    return rows.map((row) => row.id);
+  }
+
+  private async getTask(
+    filter: FederationScopeQueryFilter,
+    id: string,
+  ): Promise<FederationGetQueryResult> {
+    const row = firstRow(
+      await this.db
+        .select({
+          id: tasks.id,
+          title: tasks.title,
+          description: tasks.description,
+          status: tasks.status,
+          priority: tasks.priority,
+          projectId: tasks.projectId,
+          missionId: tasks.missionId,
+          assignee: tasks.assignee,
+          tags: tasks.tags,
+          dueDate: tasks.dueDate,
+          metadata: tasks.metadata,
+          createdAt: tasks.createdAt,
+          updatedAt: tasks.updatedAt,
+        })
+        .from(tasks)
+        .where(eq(tasks.id, id))
+        .limit(1),
+    );
+
+    if (!row) {
+      return { status: 'not_found' };
+    }
+
+    const projectIds = await this.listAccessibleProjectIds(filter);
+    const missionIds = await this.listMissionIds(projectIds);
+    if (!rowBelongsToAccessibleProjectOrMission(row, projectIds, missionIds)) {
+      return { status: 'denied', reason: 'Task is outside the federated scope' };
+    }
+
+    return { status: 'found', item: row as RowObject };
+  }
+
+  private async getNote(
+    filter: FederationScopeQueryFilter,
+    id: string,
+  ): Promise<FederationGetQueryResult> {
+    const row = firstRow(
+      await this.db
+        .select({
+          id: missionTasks.id,
+          missionId: missionTasks.missionId,
+          taskId: missionTasks.taskId,
+          userId: missionTasks.userId,
+          status: missionTasks.status,
+          content: missionTasks.notes,
+          createdAt: missionTasks.createdAt,
+          updatedAt: missionTasks.updatedAt,
+        })
+        .from(missionTasks)
+        .where(eq(missionTasks.id, id))
+        .limit(1),
+    );
+
+    if (!row || row.content === null || row.content === '') {
+      return { status: 'not_found' };
+    }
+
+    const projectIds = await this.listAccessibleProjectIds(filter);
+    const missionIds = await this.listMissionIds(projectIds);
+
+    // mission_tasks rows are user-scoped even when the mission belongs to a team.
+    // Scope-visible missions must intersect with subject ownership; team scope
+    // narrows mission IDs but never widens note reads to another user's rows.
+    if (row.userId !== filter.subjectUserId || !missionIds.includes(row.missionId)) {
+      return { status: 'denied', reason: 'Note is outside the federated scope' };
+    }
+
+    const item = { ...row } as RowObject;
+    delete item['userId'];
+    return { status: 'found', item };
+  }
+
+  private async getMemory(
+    filter: FederationScopeQueryFilter,
+    id: string,
+  ): Promise<FederationGetQueryResult> {
+    const [insightRow, preferenceRow] = await Promise.all([
+      this.db
+        .select({
+          id: insights.id,
+          userId: insights.userId,
+          kind: insights.source,
+          content: insights.content,
+          category: insights.category,
+          relevanceScore: insights.relevanceScore,
+          metadata: insights.metadata,
+          createdAt: insights.createdAt,
+          updatedAt: insights.updatedAt,
+        })
+        .from(insights)
+        .where(eq(insights.id, id))
+        .limit(1)
+        .then(firstRow),
+      this.db
+        .select({
+          id: preferences.id,
+          userId: preferences.userId,
+          kind: preferences.category,
+          key: preferences.key,
+          value: preferences.value,
+          source: preferences.source,
+          mutable: preferences.mutable,
+          createdAt: preferences.createdAt,
+          updatedAt: preferences.updatedAt,
+        })
+        .from(preferences)
+        .where(eq(preferences.id, id))
+        .limit(1)
+        .then(firstRow),
+    ]);
+
+    const candidates = [insightRow, preferenceRow].filter(
+      (row): row is NonNullable<typeof row> => row !== undefined,
+    );
+    if (candidates.length === 0) {
+      return { status: 'not_found' };
+    }
+
+    if (!filter.includePersonal) {
+      return { status: 'denied', reason: 'Memory personal rows are outside the federated scope' };
+    }
+
+    const accessible = candidates.find((row) => row.userId === filter.subjectUserId);
+    if (!accessible) {
+      return { status: 'denied', reason: 'Memory row belongs to another subject user' };
+    }
+
+    const item = { ...accessible } as RowObject;
+    delete item['userId'];
+    return { status: 'found', item };
+  }
+}

apps/gateway/src/federation/server/verbs/get.controller.ts

@@ -0,0 +1,100 @@
+/**
+ * Federation get verb (FED-M3-06).
+ *
+ * POST /api/federation/v1/get/:resource/:id
+ *
+ * Pipeline: FederationAuthGuard attaches the active grant context, then
+ * FederationScopeService enforces grant scope + native RBAC intersection, then
+ * the read-only query layer fetches one local row and tags it with `_source`.
+ * Read audit-log writes are deferred to M4; this controller does not persist
+ * request or response bodies.
+ */
+
+import { Controller, HttpException, Inject, Param, Post, Req, UseGuards } from '@nestjs/common';
+import type { FastifyRequest } from 'fastify';
+import {
+  FederationInvalidRequestError,
+  FederationNotFoundError,
+  FederationScopeViolationError,
+  FederationUnauthorizedError,
+  SOURCE_LOCAL,
+  type FederationGetResponse,
+  type SourceTag,
+} from '@mosaicstack/types';
+import { FederationAuthGuard } from '../federation-auth.guard.js';
+import '../federation-context.js';
+import { FederationScopeService } from '../scope.service.js';
+import { FederationGetQueryService } from './get-query.service.js';
+
+type FederatedRow = Record<string, unknown> & SourceTag;
+
+function scopeDenyToHttpException(deny: {
+  readonly statusCode: 400 | 403;
+  readonly message: string;
+}): HttpException {
+  const ErrorClass =
+    deny.statusCode === 400 ? FederationInvalidRequestError : FederationScopeViolationError;
+  return new HttpException(new ErrorClass(deny.message, deny).toEnvelope(), deny.statusCode);
+}
+
+@Controller('api/federation/v1/get')
+@UseGuards(FederationAuthGuard)
+export class GetController {
+  constructor(
+    @Inject(FederationScopeService) private readonly scope: FederationScopeService,
+    @Inject(FederationGetQueryService) private readonly query: FederationGetQueryService,
+  ) {}
+
+  @Post(':resource/:id')
+  async get(
+    @Param('resource') resource: string,
+    @Param('id') id: string,
+    @Req() request: FastifyRequest,
+  ): Promise<FederationGetResponse<FederatedRow>> {
+    if (!request.federationContext) {
+      throw new HttpException(
+        new FederationUnauthorizedError('Federation context missing').toEnvelope(),
+        401,
+      );
+    }
+    if (id.trim().length === 0) {
+      throw new HttpException(
+        new FederationInvalidRequestError('Federation get id must not be empty').toEnvelope(),
+        400,
+      );
+    }
+
+    const scopeResult = await this.scope.evaluateAccess({
+      context: request.federationContext,
+      resource,
+      requestedLimit: 1,
+      nativeRbac: this.query,
+    });
+
+    if (!scopeResult.allowed) {
+      throw scopeDenyToHttpException(scopeResult.deny);
+    }
+
+    const result = await this.query.get({ filter: scopeResult.filter, id });
+    if (result.status === 'not_found') {
+      throw new HttpException(
+        new FederationNotFoundError('Requested federation resource was not found').toEnvelope(),
+        404,
+      );
+    }
+    if (result.status === 'denied') {
+      throw new HttpException(
+        new FederationScopeViolationError(result.reason, {
+          resource,
+          id,
+          grantId: request.federationContext.grantId,
+          peerId: request.federationContext.peerId,
+          subjectUserId: request.federationContext.subjectUserId,
+        }).toEnvelope(),
+        403,
+      );
+    }
+
+    return { item: { ...result.item, _source: SOURCE_LOCAL } };
+  }
+}