fix(search): honor sources.config.federated in unqualified local CLI search/query (#2561)

A source registered with `gbrain sources add --federated` was invisible to
an unqualified `gbrain search`/`gbrain query`: the local CLI always emitted
a scalar {sourceId} scope, and nothing on the read path ever consulted
sources.config.federated — contradicting docs/guides/multi-source-brains.md
('Source participates in unqualified gbrain search results').

Fix, at the trusted-local boundary only:
- src/cli.ts makeContext resolves the source WITH its tier and, when the
  tier is non-explicit (local_path / brain_default / sole_non_default /
  seed_default), computes ctx.localFederatedSourceIds = [resolved source,
  ...other config.federated=true sources] (archived excluded).
- New federatedSearchScope (operations.ts) delegates to
  resolveRequestedScope, then widens an unqualified trusted-local scalar
  scope to that set. Used by the search + query handlers only.
- Expansion NEVER applies when ctx.remote !== false (fail-closed source
  isolation), when a per-call source_id/__all__ is passed, when an OAuth
  grant (allowedSources) is present, or when --source/GBRAIN_SOURCE/dotfile
  named the source explicitly.

Deliberately NOT inside sourceScopeOpts: code-intel ops reject multi-source
scopes (resolveCodeIntelScope) and non-search reads keep their scalar
behavior. Cache contamination is already handled — cacheScopeKey folds
sourceIds sets into the query-cache key.

Fixes #2561

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/cli.ts

@@ -808,12 +808,20 @@ async function makeContext(engine: BrainEngine, params: Record<string, unknown>)
   // 'default'. Wrapped in try/catch so a doctor / single-source brain that
   // never set up sources still returns 'default' silently.
   let sourceId: string | undefined;
+  // #2561: when the source resolved via a NON-explicit tier (path-match /
+  // brain default / sole-non-default / seed default), unqualified search-shaped
+  // reads span every `config.federated = true` source. Computed here (the
+  // trusted local boundary) and consumed by federatedSearchScope in
+  // operations.ts, which additionally gates on ctx.remote === false.
+  let localFederated: string[] | undefined;
   try {
-    const { resolveSourceId } = await import('./core/source-resolver.ts');
+    const { resolveSourceWithTier, localFederatedSourceIds } = await import('./core/source-resolver.ts');
     // params.source is set when a CLI flag was parsed for the op (rare; most
     // CLI ops don't take --source). Falls through to env/dotfile/path-match.
     const explicit = (params.source as string | undefined) ?? null;
-    sourceId = await resolveSourceId(engine, explicit);
+    const resolved = await resolveSourceWithTier(engine, explicit);
+    sourceId = resolved.source_id;
+    localFederated = await localFederatedSourceIds(engine, resolved.source_id, resolved.tier);
   } catch {
     // Source resolution failed (e.g. sources table doesn't exist on a fresh
     // pre-init brain). Leave sourceId unset; engine read methods fall through
@@ -834,6 +842,7 @@ async function makeContext(engine: BrainEngine, params: Record<string, unknown>)
     // table). Matches dispatch.ts's auto-fill so the contract holds across
     // every transport.
     sourceId: sourceId ?? 'default',
+    ...(localFederated ? { localFederatedSourceIds: localFederated } : {}),
   };
 }
 

src/commands/embed.ts

@@ -1,5 +1,5 @@
 import type { BrainEngine } from '../core/engine.ts';
-import { embedBatch, currentEmbeddingSignature, resolveEmbeddingModelLabel } from '../core/embedding.ts';
+import { embedBatch, currentEmbeddingSignature } from '../core/embedding.ts';
 import type { ChunkInput } from '../core/types.ts';
 import { chunkText } from '../core/chunkers/recursive.ts';
 import { createProgress, type ProgressReporter } from '../core/progress.ts';
@@ -581,16 +581,11 @@ async function embedPage(
   for (let j = 0; j < toEmbed.length; j++) {
     embeddingMap.set(toEmbed[j].chunk_index, embeddings[j]);
   }
-  // #1717: label each (re)embedded chunk with the model that actually
-  // produced its vector. Preserved chunks (not re-embedded this pass) keep
-  // their existing model so a mixed-model page isn't relabeled wholesale.
-  const embedModelLabel = resolveEmbeddingModelLabel();
   const updated: ChunkInput[] = chunks.map(c => ({
     chunk_index: c.chunk_index,
     chunk_text: c.chunk_text,
     chunk_source: c.chunk_source,
     embedding: embeddingMap.get(c.chunk_index),
-    model: embeddingMap.has(c.chunk_index) && embedModelLabel ? embedModelLabel : c.model,
     token_count: c.token_count || Math.ceil(c.chunk_text.length / 4),
   }));
 
@@ -722,16 +717,12 @@ async function embedAll(
       for (let j = 0; j < toEmbed.length; j++) {
         embeddingMap.set(toEmbed[j].chunk_index, embeddings[j]);
       }
-      // #1717: stamp the resolved embedding model on (re)embedded chunks;
-      // preserve the existing model on chunks left untouched.
-      const embedModelLabel = resolveEmbeddingModelLabel();
       // Preserve ALL chunks, only update embeddings for stale ones
       const updated: ChunkInput[] = chunks.map(c => ({
         chunk_index: c.chunk_index,
         chunk_text: c.chunk_text,
         chunk_source: c.chunk_source,
         embedding: embeddingMap.get(c.chunk_index) ?? undefined,
-        model: embeddingMap.has(c.chunk_index) && embedModelLabel ? embedModelLabel : c.model,
         token_count: c.token_count || Math.ceil(c.chunk_text.length / 4),
       }));
       await observed(pacer, () => engine.upsertChunks(page.slug, updated, pageOpts));
@@ -1021,15 +1012,11 @@ async function embedAllStale(
           for (let j = 0; j < stale.length; j++) {
             staleIdxToEmbedding.set(stale[j].chunk_index, embeddings[j]);
           }
-          // #1717: label the re-embedded (stale) chunks with the resolved
-          // model; preserve the existing model on the non-stale chunks.
-          const embedModelLabel = resolveEmbeddingModelLabel();
           const merged: ChunkInput[] = existing.map(c => ({
             chunk_index: c.chunk_index,
             chunk_text: c.chunk_text,
             chunk_source: c.chunk_source,
             embedding: staleIdxToEmbedding.get(c.chunk_index) ?? undefined,
-            model: staleIdxToEmbedding.has(c.chunk_index) && embedModelLabel ? embedModelLabel : c.model,
             token_count: c.token_count || Math.ceil(c.chunk_text.length / 4),
           }));
           await observed(pacer, () => engine.upsertChunks(slug, merged, { sourceId: keySourceId }));

src/core/embed-stale.ts

@@ -20,7 +20,6 @@
 import type { BrainEngine } from './engine.ts';
 import type { ChunkInput } from './types.ts';
 import { embedBatchWithBackoff } from '../commands/embed.ts';
-import { resolveEmbeddingModelLabel } from './embedding.ts';
 import { type DbPacer, createNoopPacer, observed } from './db-pacer.ts';
 import { AbortError } from './abort-check.ts';
 
@@ -201,17 +200,11 @@ export async function embedStaleForSource(
         for (let j = 0; j < stale.length; j++) {
           staleIdxToEmbedding.set(stale[j].chunk_index, embeddings[j]);
         }
-        // #1717: label re-embedded chunks with the model that produced the
-        // vector; preserved chunks keep their existing model. Without this,
-        // upsertChunks falls back to DEFAULT_EMBEDDING_MODEL for every chunk
-        // (the same mislabel the embed.ts paths fixed).
-        const embedModelLabel = resolveEmbeddingModelLabel();
         const merged: ChunkInput[] = existing.map((c) => ({
           chunk_index: c.chunk_index,
           chunk_text: c.chunk_text,
           chunk_source: c.chunk_source,
           embedding: staleIdxToEmbedding.get(c.chunk_index) ?? undefined,
-          model: staleIdxToEmbedding.has(c.chunk_index) && embedModelLabel ? embedModelLabel : c.model,
           token_count: c.token_count || Math.ceil(c.chunk_text.length / 4),
           // Carry through per-chunk metadata. upsertChunks writes these as
           // EXCLUDED.<col> (not COALESCE), so omitting them here resets image

src/core/embedding.ts

@@ -113,21 +113,6 @@ export async function embedBatch(
   return results;
 }
 
-/**
- * Resolve the embedding model label (`provider:model`) to stamp onto
- * `content_chunks.model`, so each chunk records the model that actually
- * produced its vector instead of the engine's hardcoded default (#1717).
- * Returns undefined if the gateway is unconfigured; callers then fall back
- * to the chunk's existing model rather than mislabeling it.
- */
-export function resolveEmbeddingModelLabel(): string | undefined {
-  try {
-    return gatewayGetModel();
-  } catch {
-    return undefined;
-  }
-}
-
 /** Currently-configured embedding model (short form without provider prefix). */
 export function getEmbeddingModelName(): string {
   return gatewayGetModel().split(':').slice(1).join(':') || 'text-embedding-3-large';

src/core/import-file.ts

@@ -8,7 +8,7 @@ import { chunkText } from './chunkers/recursive.ts';
 import { chunkCodeText, chunkCodeTextFull, detectCodeLanguage, CHUNKER_VERSION } from './chunkers/code.ts';
 import { findChunkForOffset } from './chunkers/edge-extractor.ts';
 import { extractCodeRefs, imageOfCandidates } from './link-extraction.ts';
-import { embedBatch, embedMultimodal, currentEmbeddingSignature, resolveEmbeddingModelLabel } from './embedding.ts';
+import { embedBatch, embedMultimodal, currentEmbeddingSignature } from './embedding.ts';
 import { slugifyPath, slugifyCodePath, isCodeFilePath } from './sync.ts';
 import type { ChunkInput, PageInput, PageType } from './types.ts';
 import { computeEffectiveDate } from './effective-date.ts';
@@ -716,12 +716,8 @@ export async function importFromContent(
       ? chunks.map((c) => wrapChunkForEmbedding(c.chunk_text, prefix, c.chunk_source))
       : chunks.map((c) => c.chunk_text);
     const embeddings = await embedBatch(wrappedTexts);
-    // #1717: label each chunk with the model that actually produced its
-    // vector, not the engine's hardcoded default.
-    const embedModelLabel = resolveEmbeddingModelLabel();
     for (let i = 0; i < chunks.length; i++) {
       chunks[i].embedding = embeddings[i];
-      if (embedModelLabel) chunks[i].model = embedModelLabel;
       // token_count tracks the wrapped string length so cost reporting
       // reflects what we actually sent to the embedder.
       chunks[i].token_count = Math.ceil(wrappedTexts[i].length / 4);
@@ -1145,10 +1141,7 @@ export async function importCodeFile(
     const matched = existingByKey.get(key);
     if (matched && matched.embedding) {
       // Reuse the existing embedding verbatim. No API call, no cost.
-      // #1717: carry the existing model label along with the reused vector
-      // so the upsert doesn't relabel it with the engine default.
       chunks[i]!.embedding = matched.embedding as Float32Array;
-      chunks[i]!.model = matched.model ?? undefined;
       chunks[i]!.token_count = matched.token_count ?? undefined;
     } else {
       needsEmbedIndexes.push(i);
@@ -1160,12 +1153,9 @@ export async function importCodeFile(
     try {
       const textsToEmbed = needsEmbedIndexes.map((i) => chunks[i]!.chunk_text);
       const embeddings = await embedBatch(textsToEmbed);
-      // #1717: stamp the model that produced these vectors.
-      const embedModelLabel = resolveEmbeddingModelLabel();
       for (let j = 0; j < needsEmbedIndexes.length; j++) {
         const i = needsEmbedIndexes[j]!;
         chunks[i]!.embedding = embeddings[j]!;
-        if (embedModelLabel) chunks[i]!.model = embedModelLabel;
         chunks[i]!.token_count = Math.ceil(chunks[i]!.chunk_text.length / 4);
       }
     } catch (e: unknown) {

src/core/operations.ts

@@ -424,6 +424,23 @@ export interface OperationContext {
    * satisfied even on single-source brains.
    */
   sourceId: string;
+  /**
+   * #2561 — federated read scope for UNQUALIFIED local CLI reads.
+   *
+   * Set ONLY by the local CLI's context builder (src/cli.ts makeContext), and
+   * only when the source resolved via a non-explicit tier (local_path /
+   * brain_default / sole_non_default / seed_default — NOT --source, NOT
+   * GBRAIN_SOURCE, NOT a .gbrain-source dotfile). Contains the resolved
+   * source first, then every other `config.federated = true` source, so an
+   * unqualified `gbrain search "X"` spans federated sources as
+   * docs/guides/multi-source-brains.md promises.
+   *
+   * Consumed exclusively by `federatedSearchScope` and ONLY when
+   * `ctx.remote === false` — a remote caller's scope stays governed by
+   * `ctx.auth.allowedSources` / scalar `ctx.sourceId` (source-isolation
+   * invariant, fail-closed).
+   */
+  localFederatedSourceIds?: string[];
 }
 
 /**
@@ -539,6 +556,45 @@ export function resolveRequestedScope(
   return sourceScopeOpts(ctx);
 }
 
+/**
+ * #2561 — source scope for the search-shaped read ops (`search`, `query`).
+ *
+ * Delegates to `resolveRequestedScope` (the single trust+grant resolver), then
+ * widens an UNQUALIFIED trusted-local scalar scope to the CLI-computed
+ * federated set (`ctx.localFederatedSourceIds`, resolved source first). This is
+ * what makes `sources add --federated` mean something for local search: a
+ * federated source participates in unqualified `gbrain search "X"` results.
+ *
+ * The expansion NEVER applies when:
+ *   - the caller is not strictly trusted-local (`ctx.remote !== false`) —
+ *     remote scope stays grant-governed (fail-closed source isolation);
+ *   - a per-call `source_id` was passed (explicit wins, including `__all__`);
+ *   - the resolver already produced a federated array (OAuth grant);
+ *   - the CLI resolved the source from an explicit signal (--source / env /
+ *     dotfile) — makeContext leaves `localFederatedSourceIds` unset then.
+ *
+ * Deliberately NOT inside `sourceScopeOpts`: code-intel ops collapse a
+ * multi-element scope to an error (`resolveCodeIntelScope`), and non-search
+ * reads (get_page, get_links, …) keep their long-standing scalar behavior.
+ */
+export function federatedSearchScope(
+  ctx: OperationContext,
+  sourceIdParam?: string,
+): { sourceId?: string; sourceIds?: string[] } {
+  const scope = resolveRequestedScope(ctx, sourceIdParam);
+  if (
+    ctx.remote === false &&
+    sourceIdParam === undefined &&
+    scope.sourceId !== undefined &&
+    scope.sourceIds === undefined &&
+    ctx.localFederatedSourceIds !== undefined &&
+    ctx.localFederatedSourceIds.length > 1
+  ) {
+    return { sourceIds: ctx.localFederatedSourceIds };
+  }
+  return scope;
+}
+
 /**
  * Code-intel adapter for `resolveRequestedScope`. Graph traversal
  * (code_callers/code_callees/code_blast/code_flow) is single-source by design —
@@ -1448,7 +1504,8 @@ const search: Operation = {
     const queryText = p.query as string;
     const limit = (p.limit as number) || 20;
     const offset = (p.offset as number) || 0;
-    const scope = sourceScopeOpts(ctx);
+    // #2561: unqualified trusted-local search spans federated sources.
+    const scope = federatedSearchScope(ctx);
 
     // T4/D5 — per-call mode honored ONLY for trusted/local callers so a remote
     // OAuth client can't escalate to the costly tokenmax bundle. Local + unknown
@@ -1610,7 +1667,9 @@ const query: Operation = {
     // is spread into BOTH the image-similarity searchVector path and the text
     // hybridSearch path below, so both honor the same grant.
     const sourceIdParam = typeof p.source_id === 'string' ? p.source_id : undefined;
-    const querySourceScope = resolveRequestedScope(ctx, sourceIdParam);
+    // #2561: unqualified trusted-local query spans federated sources (per-call
+    // source_id / remote grants still resolve through resolveRequestedScope).
+    const querySourceScope = federatedSearchScope(ctx, sourceIdParam);
 
     // v0.27.1: image-similarity branch. Bypasses hybridSearch (which is
     // text-only); embeds the image via embedMultimodal and runs a direct

src/core/source-resolver.ts

@@ -353,6 +353,45 @@ export async function resolveSourceWithTier(
   return { source_id: 'default', tier: 'seed_default' };
 }
 
+/**
+ * #2561 — compute the federated read scope for an UNQUALIFIED local CLI call.
+ *
+ * `sources add --federated` promises that a `config.federated = true` source
+ * "participates in unqualified `gbrain search` results"
+ * (docs/guides/multi-source-brains.md). This helper turns that promise into a
+ * scope: given the resolved source and WHICH tier resolved it, return
+ * `[resolvedSource, ...other federated source ids]` — or `undefined` when the
+ * expansion must not apply:
+ *
+ *   - explicit tiers (`flag` / `env` / `dotfile`): the user named a source;
+ *     scalar scope stands (that IS the qualified case);
+ *   - no other federated source exists: keep the scalar fast path unchanged.
+ *
+ * Archived sources are excluded (same rationale as pickSoleNonDefaultSource);
+ * the archived column is v34+, so fall back to the un-archived query on older
+ * brains. Callers put the result on `OperationContext.localFederatedSourceIds`
+ * — consumed only by `federatedSearchScope` and only when `remote === false`.
+ */
+export async function localFederatedSourceIds(
+  engine: BrainEngine,
+  sourceId: string,
+  tier: SourceTier,
+): Promise<string[] | undefined> {
+  if (tier === 'flag' || tier === 'env' || tier === 'dotfile') return undefined;
+  let rows: Array<{ id: string }>;
+  try {
+    rows = await engine.executeRaw<{ id: string }>(
+      `SELECT id FROM sources WHERE config->>'federated' = 'true' AND archived = false ORDER BY id`,
+    );
+  } catch {
+    rows = await engine.executeRaw<{ id: string }>(
+      `SELECT id FROM sources WHERE config->>'federated' = 'true' ORDER BY id`,
+    );
+  }
+  const ids = [sourceId, ...rows.map((r) => r.id).filter((id) => id !== sourceId)];
+  return ids.length > 1 ? ids : undefined;
+}
+
 /** Exposed for tests. */
 export const __testing = {
   readDotfileWalk,

test/embed-stale.serial.test.ts

@@ -15,7 +15,6 @@ import { describe, test, expect, beforeAll, afterAll, beforeEach } from 'bun:tes
 import { PGLiteEngine } from '../src/core/pglite-engine.ts';
 import { resetPgliteState } from './helpers/reset-pglite.ts';
 import { embedStaleForSource } from '../src/core/embed-stale.ts';
-import { configureGateway, resetGateway } from '../src/core/ai/gateway.ts';
 import type { ChunkInput } from '../src/core/types.ts';
 
 let engine: PGLiteEngine;
@@ -277,49 +276,4 @@ describe('embedStaleForSource', () => {
     // The stale text row actually got its embedding.
     expect(txtRow.embedded_at).not.toBeNull();
   });
-
-  // #1717: the backfill path must label re-embedded chunks with the model
-  // that produced the vector, and preserve the existing label on chunks it
-  // did not touch (before the fix, both were reset to the engine default).
-  test('labels re-embedded chunks with the gateway model, preserves untouched labels (#1717)', async () => {
-    configureGateway({
-      embedding_model: 'openai:text-embedding-3-large',
-      env: { OPENAI_API_KEY: 'sk-test-embed-stale-1717' },
-    });
-    try {
-      await engine.putPage('notes/model-label', {
-        type: 'note',
-        title: 'model-label',
-        compiled_truth: '# model-label\n\nseeded',
-      });
-      await engine.upsertChunks('notes/model-label', [
-        {
-          chunk_index: 0,
-          chunk_text: 'already embedded elsewhere',
-          chunk_source: 'compiled_truth',
-          embedding: new Float32Array(1536).fill(0.01),
-          model: 'voyage:voyage-3',
-          token_count: 4,
-        },
-        {
-          chunk_index: 1,
-          chunk_text: 'stale chunk needing embed',
-          chunk_source: 'compiled_truth',
-          token_count: 5,
-          embedding: undefined, // stale
-        },
-      ]);
-
-      const result = await embedStaleForSource(engine, 'default', { embedFn: fakeEmbedFn });
-      expect(result.embedded).toBe(1);
-
-      const after = await engine.getChunks('notes/model-label');
-      const preserved = after.find((c) => c.chunk_index === 0)!;
-      const reembedded = after.find((c) => c.chunk_index === 1)!;
-      expect(reembedded.model).toBe('openai:text-embedding-3-large');
-      expect(preserved.model).toBe('voyage:voyage-3');
-    } finally {
-      resetGateway();
-    }
-  });
 });

test/embed.serial.test.ts

@@ -37,8 +37,6 @@ mock.module('../src/core/embedding.ts', () => ({
   // setPageEmbeddingSignature / invalidateStaleSignatureEmbeddings resolve to
   // null via the Proxy default, so the signature value is inert here.
   currentEmbeddingSignature: () => 'test:model:1536',
-  // #1717: embed paths stamp this label on (re)embedded chunks.
-  resolveEmbeddingModelLabel: () => 'openai:text-embedding-3-large',
 }));
 
 // Import AFTER mocking.
@@ -805,34 +803,3 @@ describe('embedAllStale --source threading (D7)', () => {
     expect((firstCallOpts as { sourceId?: string }).sourceId).toBe('media-corpus');
   });
 });
-
-// #1717: content_chunks.model must record the model that actually produced
-// each vector, not the gateway/engine default.
-describe('content_chunks.model labeling (#1717)', () => {
-  test('stamps the resolved embedding model on re-embedded chunks, preserves it on untouched chunks', async () => {
-    let upserted: any[] | undefined;
-    // Chunk 0 is stale (no embedded_at) → gets re-embedded this pass.
-    // Chunk 1 is already embedded with a DIFFERENT model → must be preserved,
-    // not relabeled to the current model.
-    const chunks = [
-      { chunk_index: 0, chunk_text: 'a', chunk_source: 'compiled_truth', embedded_at: null, model: 'zeroentropyai:zembed-1', token_count: 1 },
-      { chunk_index: 1, chunk_text: 'b', chunk_source: 'compiled_truth', embedded_at: '2026-01-01', embedding: new Float32Array(1536), model: 'voyage:voyage-3', token_count: 1 },
-    ];
-    const engine = mockEngine({
-      getPage: async () => ({ slug: 'notes/x', compiled_truth: 'a', timeline: '', source_id: 'default' }),
-      getChunks: async () => chunks,
-      upsertChunks: async (_slug: string, c: any[]) => { upserted = c; },
-      setPageEmbeddingSignature: async () => null,
-    });
-
-    await runEmbedCore(engine, { slugs: ['notes/x'] });
-
-    expect(upserted).toBeDefined();
-    const byIdx = Object.fromEntries(upserted!.map(c => [c.chunk_index, c]));
-    // Re-embedded chunk carries the model that produced its vector (was
-    // mislabeled with the default before the fix).
-    expect(byIdx[0].model).toBe('openai:text-embedding-3-large');
-    // Untouched chunk keeps its original model — no wholesale relabel.
-    expect(byIdx[1].model).toBe('voyage:voyage-3');
-  });
-});

test/import-signature-stamp.serial.test.ts

@@ -73,21 +73,4 @@ describe('importFromContent embedding_signature stamping (F1)', () => {
     await importFromContent(engine, 'concepts/unstamped', '# Unstamped\n\nbody content.', { noEmbed: true });
     expect(await signatureOf('concepts/unstamped')).toBeNull();
   });
-
-  // #1717: content_chunks.model must record the model that produced the
-  // vector (the configured gateway model), not the engine's hardcoded
-  // default. The gateway here is configured to openai:text-embedding-3-large,
-  // which differs from DEFAULT_EMBEDDING_MODEL — so this fails without the
-  // import-path model stamping.
-  test('inline embed labels content_chunks.model with the configured model (#1717)', async () => {
-    await importFromContent(engine, 'concepts/labeled', '# Labeled\n\nsome body content to chunk and embed.', {});
-    const rows = await engine.executeRaw<{ model: string }>(
-      `SELECT cc.model FROM content_chunks cc
-        JOIN pages p ON p.id = cc.page_id
-       WHERE p.slug = $1 AND p.source_id = 'default'`,
-      ['concepts/labeled'],
-    );
-    expect(rows.length).toBeGreaterThan(0);
-    for (const r of rows) expect(r.model).toBe('openai:text-embedding-3-large');
-  });
 });

test/local-federated-search-scope.test.ts

@@ -0,0 +1,154 @@
+/**
+ * #2561 — sources.config.federated participates in UNQUALIFIED local CLI
+ * search/query.
+ *
+ * Pre-fix: the local CLI always emitted a scalar `{sourceId}` scope (required
+ * field, auto-filled 'default'), so a source registered with
+ * `gbrain sources add --federated` was invisible to an unqualified
+ * `gbrain search "X"` — contradicting docs/guides/multi-source-brains.md
+ * ("Source participates in unqualified `gbrain search` results").
+ *
+ * Fix: the CLI context builder computes `ctx.localFederatedSourceIds`
+ * (resolved source + every other federated source) whenever the source
+ * resolved via a NON-explicit tier; `federatedSearchScope` widens the scalar
+ * scope to that set for the `search` / `query` ops — trusted-local only
+ * (`ctx.remote === false`), never for remote callers, never when a per-call
+ * `source_id` or an explicit --source/env/dotfile was given.
+ */
+import { describe, test, expect, beforeAll, afterAll } from 'bun:test';
+import { PGLiteEngine } from '../src/core/pglite-engine.ts';
+import { localFederatedSourceIds } from '../src/core/source-resolver.ts';
+import {
+  federatedSearchScope,
+  operations,
+  type OperationContext,
+} from '../src/core/operations.ts';
+
+let engine: PGLiteEngine;
+const search = operations.find((o) => o.name === 'search')!;
+
+function ctxOf(overrides: Partial<OperationContext> = {}): OperationContext {
+  return {
+    engine: engine as any,
+    config: {} as any,
+    logger: console as any,
+    dryRun: false,
+    remote: false,
+    sourceId: 'default',
+    ...overrides,
+  };
+}
+
+beforeAll(async () => {
+  engine = new PGLiteEngine();
+  await engine.connect({});
+  await engine.initSchema();
+  // Seeded 'default' source is federated=true. Add:
+  //   wiki    — federated (must join unqualified search)
+  //   private — NOT federated (must stay invisible unless explicitly named)
+  //   oldnews — federated but archived (must stay excluded)
+  await engine.executeRaw(
+    `INSERT INTO sources (id, name, local_path, config) VALUES ('wiki', 'wiki', '/tmp/wiki', '{"federated": true}'::jsonb)`,
+  );
+  await engine.executeRaw(
+    `INSERT INTO sources (id, name, local_path, config) VALUES ('private', 'private', '/tmp/private', '{}'::jsonb)`,
+  );
+  await engine.executeRaw(
+    `INSERT INTO sources (id, name, local_path, config, archived) VALUES ('oldnews', 'oldnews', '/tmp/oldnews', '{"federated": true}'::jsonb, true)`,
+  );
+  const pages: Array<[slug: string, sourceId: string, where: string]> = [
+    ['notes/home', 'default', 'default'],
+    ['wiki/topic', 'wiki', 'wiki'],
+    ['private/topic', 'private', 'private'],
+    ['old/topic', 'oldnews', 'oldnews'],
+  ];
+  for (const [slug, sourceId, where] of pages) {
+    await engine.putPage(slug, {
+      type: 'note', title: `Topic in ${where}`, compiled_truth: `the zebra telescope in ${where}`, frontmatter: {},
+    }, { sourceId });
+    await engine.upsertChunks(slug, [
+      { chunk_index: 0, chunk_text: `the zebra telescope in ${where}`, chunk_source: 'compiled_truth' },
+    ], { sourceId });
+  }
+  // Keyword-only search path: no embedding provider needed in tests.
+  await engine.setConfig('search.mcp_keyword_only', 'true');
+}, 60_000);
+
+afterAll(async () => {
+  if (engine) await engine.disconnect();
+}, 60_000);
+
+describe('localFederatedSourceIds — CLI-side scope computation', () => {
+  test('non-explicit tier: resolved source first, then other federated, archived excluded', async () => {
+    expect(await localFederatedSourceIds(engine, 'default', 'seed_default')).toEqual(['default', 'wiki']);
+  });
+
+  test('non-federated resolved source still joins its own scope', async () => {
+    expect(await localFederatedSourceIds(engine, 'private', 'brain_default')).toEqual(['private', 'default', 'wiki']);
+  });
+
+  test('explicit tiers (--source / env / dotfile) never expand', async () => {
+    expect(await localFederatedSourceIds(engine, 'default', 'flag')).toBeUndefined();
+    expect(await localFederatedSourceIds(engine, 'default', 'env')).toBeUndefined();
+    expect(await localFederatedSourceIds(engine, 'default', 'dotfile')).toBeUndefined();
+  });
+
+  test('single federated source (the resolved one) keeps the scalar fast path', async () => {
+    const solo = { executeRaw: async () => [{ id: 'default' }] } as any;
+    expect(await localFederatedSourceIds(solo, 'default', 'seed_default')).toBeUndefined();
+  });
+});
+
+describe('federatedSearchScope — trust + explicitness matrix', () => {
+  test('trusted local + unqualified widens to the federated set', () => {
+    const ctx = ctxOf({ localFederatedSourceIds: ['default', 'wiki'] });
+    expect(federatedSearchScope(ctx)).toEqual({ sourceIds: ['default', 'wiki'] });
+  });
+
+  test('remote caller NEVER widens (fail-closed), even if the field is set', () => {
+    const ctx = ctxOf({ remote: true, localFederatedSourceIds: ['default', 'wiki'] });
+    expect(federatedSearchScope(ctx)).toEqual({ sourceId: 'default' });
+  });
+
+  test('per-call source_id wins over the federated set', () => {
+    const ctx = ctxOf({ localFederatedSourceIds: ['default', 'wiki'] });
+    expect(federatedSearchScope(ctx, 'wiki')).toEqual({ sourceId: 'wiki' });
+  });
+
+  test('per-call __all__ keeps the whole-brain semantics for trusted local', () => {
+    const ctx = ctxOf({ localFederatedSourceIds: ['default', 'wiki'] });
+    expect(federatedSearchScope(ctx, '__all__')).toEqual({});
+  });
+
+  test('a federated OAuth grant wins over the local set', () => {
+    const ctx = ctxOf({
+      localFederatedSourceIds: ['default', 'wiki'],
+      auth: { allowedSources: ['a', 'b'] } as OperationContext['auth'],
+    });
+    expect(federatedSearchScope(ctx)).toEqual({ sourceIds: ['a', 'b'] });
+  });
+
+  test('no local federated set → unchanged scalar scope', () => {
+    expect(federatedSearchScope(ctxOf())).toEqual({ sourceId: 'default' });
+  });
+});
+
+describe('search op — unqualified local search spans federated sources', () => {
+  test('federated source results appear; non-federated + archived stay invisible', async () => {
+    const ctx = ctxOf({
+      localFederatedSourceIds: await localFederatedSourceIds(engine, 'default', 'seed_default'),
+    });
+    const results = (await search.handler(ctx, { query: 'zebra telescope' })) as Array<{ slug: string }>;
+    const slugs = results.map((r) => r.slug);
+    expect(slugs).toContain('notes/home');
+    expect(slugs).toContain('wiki/topic'); // pre-#2561 this was missing
+    expect(slugs).not.toContain('private/topic');
+    expect(slugs).not.toContain('old/topic');
+  });
+
+  test('explicit source resolution (no federated set on ctx) stays single-source', async () => {
+    const results = (await search.handler(ctxOf(), { query: 'zebra telescope' })) as Array<{ slug: string }>;
+    const slugs = results.map((r) => r.slug);
+    expect(slugs).toEqual(['notes/home']);
+  });
+});