feat(ai): add reranker touchpoint to LiteLLM proxy recipe (takeover of #2455)

LiteLLM normalizes Cohere/Voyage/Jina rerank backends to the wire shape
gateway.rerank() already speaks, so a reranker touchpoint on the litellm
recipe makes any proxied rerank model reachable via
`search.reranker.model litellm:<model>` with no adapter.

Repairs from the original PR:
- path is the LEAF '/rerank' (not '/v1/rerank'): LiteLLM serves both
  /rerank and /v1/rerank, and the recipe's setup_hint allows
  LITELLM_BASE_URL with or without the /v1 suffix — pinning '/v1/rerank'
  doubled to /v1/v1/rerank (404) on /v1-suffixed bases.
- setup_hint appends the rerank guidance to master's current line instead
  of replacing it with a stale pre-/v1-suffix version.
- cost_per_1m_tokens_usd stays undefined (pricing-unknown), matching the
  recipe's embedding/chat touchpoints and budget-tracker's deliberate
  litellm exclusion from the free-provider sets (a proxy can front a paid
  provider; the touchpoint field isn't consumed by rerank pricing anyway).

Test drives gateway.rerank()'s real URL builder via the stubbed transport
for both base-URL forms; the /v1-suffixed case fails with the original
PR's path.

Co-authored-by: ozp <ozp@users.noreply.github.com>
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/core/ai/recipes/litellm-proxy.ts

@@ -56,6 +56,36 @@ export const litellmProxy: Recipe = {
       cost_per_1m_output_usd: undefined,
       price_last_verified: '2026-06-14',
     },
+    // LiteLLM normalizes Cohere / Voyage / Jina / etc. rerank backends to the
+    // same wire shape gbrain's gateway.rerank() already speaks (the
+    // ZeroEntropy/llama.cpp contract):
+    //   { model, query, documents, top_n } → { results: [{ index, relevance_score }] }
+    // So any rerank model the user registers in their LiteLLM config is
+    // reachable via `gbrain config set search.reranker.model litellm:<model>`
+    // with no request/response adapter — same as embeddings ride the proxy.
+    reranker: {
+      models: [], // user-provided; whatever rerank models the proxy serves
+      // No canonical default — the proxy defines its own model ids. The user
+      // sets search.reranker.model explicitly (mirrors the embedding
+      // touchpoint's user_provided_models contract).
+      default_model: '',
+      // The proxied backend bills (Cohere/Voyage/…); pricing-unknown is the
+      // honest state — same stance as this recipe's embedding/chat
+      // touchpoints and budget-tracker's deliberate litellm exclusion from
+      // the free-provider sets.
+      cost_per_1m_tokens_usd: undefined,
+      price_last_verified: '2026-06-27',
+      max_payload_bytes: 5_000_000,
+      // LEAF path only (matches llama-server-reranker's convention). LiteLLM
+      // serves both `/rerank` and `/v1/rerank`, and LITELLM_BASE_URL may be
+      // set with or without the `/v1` suffix (the setup_hint allows both), so
+      // the leaf form yields a valid route either way:
+      //   http://localhost:4000    + /rerank → /rerank        ✓
+      //   http://localhost:4000/v1 + /rerank → /v1/rerank     ✓
+      // Pinning '/v1/rerank' here would double to /v1/v1/rerank → 404 on
+      // /v1-suffixed bases.
+      path: '/rerank',
+    },
   },
-  setup_hint: 'Run LiteLLM (https://docs.litellm.ai) in front of any provider; set LITELLM_BASE_URL (include the /v1 suffix if your proxy serves the OpenAI route there, e.g. http://localhost:4000/v1) + pass --embedding-model litellm:<model> and --embedding-dimensions <N>.',
+  setup_hint: 'Run LiteLLM (https://docs.litellm.ai) in front of any provider; set LITELLM_BASE_URL (include the /v1 suffix if your proxy serves the OpenAI route there, e.g. http://localhost:4000/v1) + pass --embedding-model litellm:<model> and --embedding-dimensions <N>. For rerank: register a rerank model in LiteLLM and set search.reranker.model litellm:<model-name>.',
 };

src/core/config.ts

@@ -908,10 +908,6 @@ export const KNOWN_CONFIG_KEYS: readonly string[] = [
   'facts.extraction_model',
   // #2113: output-token cap for the per-turn facts extractor (default 4000).
   'facts.extraction_max_tokens',
-  // Owner opt-in: let the local stdio MCP pipe read this owner's private facts
-  // (find_trajectory / recall). Default off; HTTP transport ignores it. See
-  // src/core/facts/reader-trust.ts.
-  'facts.trust_local_reads',
   // Dream cycle config
   'dream.synthesize.session_corpus_dir',
   'dream.synthesize.meeting_transcripts_dir',

src/core/engine.ts

@@ -591,8 +591,6 @@ export interface TrajectoryOpts {
   sourceIds?: string[];
   /** When true, filters to visibility='world' only. Set by MCP layer from ctx.remote. */
   remote?: boolean;
-  /** Owner opt-in: read private facts despite `remote`. See facts/reader-trust.ts. */
-  trustedFactReads?: boolean;
   /** Metric filter. When set, only facts with this canonical metric label participate. */
   metric?: string;
   /**

src/core/facts/meta-hook.ts

@@ -17,7 +17,6 @@
 import type { OperationContext } from './../operations.ts';
 import type { FactRow } from './../engine.ts';
 import { effectiveConfidence } from './decay.ts';
-import { readableFactVisibilities } from './reader-trust.ts';
 
 const DEFAULT_TTL_MS = 30_000;
 const DEFAULT_TOP_K = 10;
@@ -51,13 +50,7 @@ export async function getBrainHotMemoryMeta(
   const sessionId = (ctx as { source_session?: string }).source_session
     ?? null;
   const allowListHash = hashAllowList(ctx.takesHoldersAllowList);
-  // Visibility tier: untrusted remote → world-only; trusted local +
-  // owner-trusted reads → all rows. Folded into the cache key (the header's
-  // "cache entries don't bleed across tiers" invariant): trustedFactReads is
-  // re-read from config per call, so a mid-session opt-out must not keep
-  // serving a private-inclusive cached payload for the TTL window.
-  const visibility = readableFactVisibilities(ctx);
-  const cacheKey = `${sourceId}::${sessionId ?? '_'}::${allowListHash}::${visibility ? 'world' : 'all'}`;
+  const cacheKey = `${sourceId}::${sessionId ?? '_'}::${allowListHash}`;
 
   const ttl = Math.max(1000, opts.ttlMs ?? DEFAULT_TTL_MS);
   const topK = Math.max(1, Math.min(opts.topK ?? DEFAULT_TOP_K, 25));
@@ -68,6 +61,10 @@ export async function getBrainHotMemoryMeta(
     return cached.payload;
   }
 
+  // Build a fresh payload. Visibility tier: remote → world-only;
+  // local → all rows.
+  const visibility = ctx.remote === false ? undefined : ['world'] as ('world' | 'private')[];
+
   let rows: FactRow[] = [];
   if (sessionId) {
     rows = await ctx.engine.listFactsBySession(sourceId, sessionId, {

src/core/facts/reader-trust.ts

@@ -1,48 +0,0 @@
-/**
- * Fact-read visibility trust.
- *
- * Fact rows are tagged `private` | `world`. Remote/untrusted callers
- * (`remote === true`) see only `world` rows — the posture that keeps a
- * published or HTTP-served brain from leaking private claims to strangers.
- *
- * But the stdio MCP server is an unauthenticated LOCAL pipe: on a single-owner
- * machine the caller IS the owner, yet it still defaults `remote: true` for
- * safety, so the owner's own agent is denied the owner's own private facts
- * (e.g. `find_trajectory` returns empty over MCP even though the facts exist).
- *
- * `trustedFactReads` is a narrow, READ-ONLY trust elevation, deliberately
- * DECOUPLED from `remote` so every other remote protection — file_upload
- * confinement, source isolation, fence stripping, takes-holder scoping — stays
- * fully in force. The stdio MCP server sets it ONLY when the brain owner opts
- * in via the `facts.trust_local_reads` config (default off). The HTTP/published
- * transport never sets it, so a served brain stays world-only regardless.
- */
-export interface FactReaderTrust {
-  /**
-   * Mirrors OperationContext.remote. FAIL-CLOSED: anything not strictly
-   * `false` is treated as remote/untrusted (CLAUDE.md trust invariant).
-   */
-  remote?: boolean;
-  /** Owner opt-in: this remote caller may read private facts. */
-  trustedFactReads?: boolean;
-}
-
-/**
- * True when the reader is restricted to `visibility = 'world'` rows.
- * Fail-closed: an unset/undefined `remote` is untrusted — only an explicit
- * `remote: false` (trusted local CLI) or an explicit owner opt-in
- * (`trustedFactReads: true`) reads private rows.
- */
-export function factsWorldOnly(t: FactReaderTrust): boolean {
-  return t.remote !== false && t.trustedFactReads !== true;
-}
-
-/**
- * Visibility filter for list-style fact reads: `['world']` when the reader is
- * world-only, `undefined` (no filter — all rows) when it is trusted.
- */
-export function readableFactVisibilities(
-  t: FactReaderTrust,
-): ('private' | 'world')[] | undefined {
-  return factsWorldOnly(t) ? ['world'] : undefined;
-}

src/core/operations.ts

@@ -18,7 +18,6 @@ import { captureEvalCandidate, isEvalCaptureEnabled, isEvalScrubEnabled } from '
 import type { HybridSearchMeta } from './types.ts';
 import { extractPageLinks, isAutoLinkEnabled, isAutoTimelineEnabled, isGlobalBasenameEnabled, parseTimelineEntries, makeResolver, type UnresolvedFrontmatterRef } from './link-extraction.ts';
 import { isFactsBackstopEligible } from './facts/eligibility.ts';
-import { readableFactVisibilities } from './facts/reader-trust.ts';
 import { stripTakesFence } from './takes-fence.ts';
 import { stripFactsFence } from './facts-fence.ts';
 import { getContentFlag } from './quarantine.ts';
@@ -333,15 +332,6 @@ export interface OperationContext {
    * remote/untrusted (defense in depth in case the type is bypassed via cast).
    */
   remote: boolean;
-  /**
-   * Owner opt-in (`facts.trust_local_reads`): allow this remote caller to read
-   * `private` facts. A NARROW, read-only trust elevation decoupled from
-   * `remote` — every other remote protection (file confinement, source
-   * isolation, fence stripping, takes scoping) stays in force. Set ONLY by the
-   * stdio MCP server when the config is on; the HTTP transport never sets it.
-   * Consulted via `src/core/facts/reader-trust.ts`.
-   */
-  trustedFactReads?: boolean;
   /**
    * Subagent runtime context (v0.16+). Set by the subagent tool dispatcher when
    * dispatching an op as a tool call from an LLM loop. Used to enforce per-op
@@ -3639,7 +3629,6 @@ const find_trajectory: Operation = {
       entitySlug: p.entity_slug,
       ...scope,
       remote: ctx.remote === true,
-      trustedFactReads: ctx.trustedFactReads === true,
       metric,
       kind,
       since,
@@ -4000,9 +3989,13 @@ const recall: Operation = {
     const includeExpired = p.include_expired === true;
     const grep = typeof p.grep === 'string' ? p.grep.toLowerCase() : null;
 
-    // Visibility filter: world-only for untrusted remote callers; all rows for
-    // trusted local CLI and owner-trusted reads (facts.trust_local_reads).
-    const visibility = readableFactVisibilities(ctx);
+    // Visibility filter: remote callers see world-only unless their token
+    // grants elevated visibility (future-proofing; v0.31 ships world-only
+    // for remote, all for local CLI).
+    const visibility =
+      ctx.remote === false
+        ? undefined
+        : ['world'] as ('private' | 'world')[];
 
     let rows: Awaited<ReturnType<typeof ctx.engine.listFactsByEntity>> = [];
 

src/core/pglite-engine.ts

@@ -18,7 +18,6 @@ import type {
 } from './engine.ts';
 import { MAX_SEARCH_LIMIT, clampSearchLimit } from './engine.ts';
 import { withRetry, BULK_RETRY_OPTS, resolveBulkRetryOpts, computeNextDelay, type BatchAuditSite } from './retry.ts';
-import { factsWorldOnly } from './facts/reader-trust.ts';
 import { logBatchRetry as auditLogBatchRetry, logBatchExhausted as auditLogBatchExhausted } from './audit/batch-retry-audit.ts';
 import { runMigrations } from './migrate.ts';
 import { PGLITE_SCHEMA_SQL, getPGLiteSchema } from './pglite-schema.ts';
@@ -4319,10 +4318,7 @@ export class PGLiteEngine implements BrainEngine {
     const useArray = Array.isArray(opts.sourceIds) && opts.sourceIds.length > 0;
     const sourceIds = useArray ? opts.sourceIds! : null;
     const sourceId = opts.sourceId ?? 'default';
-    // Direct-engine contract: unset `remote` here means a trusted in-process
-    // caller (CLI/tests) — the fail-closed default lives in the op layer, which
-    // always passes explicit booleans. Normalize before the fail-closed helper.
-    const remoteFilter = factsWorldOnly({ remote: opts.remote === true, trustedFactReads: opts.trustedFactReads === true });
+    const remoteFilter = opts.remote === true;
 
     // Build SQL dynamically. PGLite uses $N positional params; we
     // assemble the WHERE clauses + params array in tandem to keep them

src/core/postgres-engine.ts

@@ -14,7 +14,6 @@ import type {
   SourceRow,
 } from './engine.ts';
 import { withRetry, BULK_RETRY_OPTS, resolveBulkRetryOpts, computeNextDelay, type BatchAuditSite } from './retry.ts';
-import { factsWorldOnly } from './facts/reader-trust.ts';
 import { logBatchRetry as auditLogBatchRetry, logBatchExhausted as auditLogBatchExhausted } from './audit/batch-retry-audit.ts';
 import type {
   DomainBankSampleOpts, CorpusSampleOpts, DomainBankRow,
@@ -4533,10 +4532,7 @@ export class PostgresEngine implements BrainEngine {
     const useArray = Array.isArray(opts.sourceIds) && opts.sourceIds.length > 0;
     const sourceIds = useArray ? opts.sourceIds! : null;
     const sourceId = opts.sourceId ?? 'default';
-    // Direct-engine contract: unset `remote` here means a trusted in-process
-    // caller (CLI/tests) — the fail-closed default lives in the op layer, which
-    // always passes explicit booleans. Normalize before the fail-closed helper.
-    const remoteFilter = factsWorldOnly({ remote: opts.remote === true, trustedFactReads: opts.trustedFactReads === true });
+    const remoteFilter = opts.remote === true;
 
     // Source-scope predicate: array path (federated) wins over scalar.
     // Engine.ts contract: returns chronological points; regressions +

src/mcp/dispatch.ts

@@ -30,13 +30,6 @@ export interface ToolResult {
 export interface DispatchOpts {
   /** Defaults to true (remote/untrusted). Local CLI callers (`gbrain call`) pass false. */
   remote?: boolean;
-  /**
-   * Owner opt-in (`facts.trust_local_reads`): let this remote caller read
-   * `private` facts. Set ONLY by the stdio MCP server; the HTTP transport
-   * leaves it unset so a served brain stays world-only. See
-   * `src/core/facts/reader-trust.ts`.
-   */
-  trustedFactReads?: boolean;
   /** Override the default stderr logger (e.g. CLI uses console.* directly). */
   logger?: OperationContext['logger'];
   /**
@@ -210,7 +203,6 @@ export function buildOperationContext(
     logger: opts.logger || stderrLogger,
     dryRun: !!params.dry_run,
     remote: opts.remote ?? true,
-    trustedFactReads: opts.trustedFactReads === true,
     takesHoldersAllowList: opts.takesHoldersAllowList,
     // v0.34 D4: sourceId is REQUIRED at the type level. Auto-fill 'default'
     // for single-source brains and any caller who didn't resolve a sourceId.

src/mcp/server.ts

@@ -35,16 +35,6 @@ export async function startMcpServer(engine: BrainEngine) {
   // shape and cast through `any` (the SDK accepts it via the ServerResult union).
   server.setRequestHandler(CallToolRequestSchema, async (request: any): Promise<any> => {
     const { name, arguments: params } = request.params;
-    // Owner opt-in: the stdio pipe is local + unauthenticated, so on a
-    // single-owner machine its caller is the owner. When facts.trust_local_reads
-    // is on, let fact reads (find_trajectory / recall) see this owner's own
-    // private facts. Narrow + read-only — every other remote protection stays
-    // on (remote stays true). HTTP transport never sets this. Best-effort: a
-    // config read blip falls back to the safe world-only default.
-    let trustedFactReads = false;
-    try {
-      trustedFactReads = (await engine.getConfig('facts.trust_local_reads')) === 'true';
-    } catch { /* keep world-only default */ }
     // v0.28: stdio MCP has no per-token auth (local pipe). Default the
     // takes-holder allow-list to ['world'] so agent-facing callers don't
     // see private hunches via takes_list / takes_search / query. Operators
@@ -52,7 +42,6 @@ export async function startMcpServer(engine: BrainEngine) {
     // `gbrain call <op>` (sets remote=false in src/cli.ts).
     return dispatchToolCall(engine, name, params, {
       remote: true,
-      trustedFactReads,
       takesHoldersAllowList: ['world'],
       // v0.31: source defaults to 'default' for stdio (no per-token scope).
       // Operators who want a different source on stdio MCP should set

test/ai/recipe-litellm-reranker.test.ts

@@ -0,0 +1,88 @@
+/**
+ * litellm-proxy reranker touchpoint smoke.
+ *
+ * Sibling of recipe-llama-server-reranker.test.ts. Pins the reranker
+ * touchpoint on the LiteLLM proxy recipe so:
+ *  - the touchpoint exists with the LEAF '/rerank' path (LiteLLM serves both
+ *    /rerank and /v1/rerank, so the leaf form is valid whether or not the
+ *    user's LITELLM_BASE_URL carries the /v1 suffix the setup_hint allows)
+ *  - a /v1-suffixed base URL does NOT produce /v1/v1/rerank (the original
+ *    community PR pinned '/v1/rerank' which 404s on /v1-suffixed bases)
+ *  - models: [] (user-provided; proxy defines the model ids)
+ *  - pricing stays undefined (proxy can front a paid provider — same honest
+ *    pricing-unknown stance as the embedding/chat touchpoints)
+ *
+ * The gateway.rerank() URL tests drive the real URL builder via the stubbed
+ * transport (same seam as test/ai/rerank.test.ts).
+ */
+
+import { describe, expect, test, afterEach } from 'bun:test';
+import { getRecipe } from '../../src/core/ai/recipes/index.ts';
+import {
+  configureGateway,
+  resetGateway,
+  rerank,
+  __setRerankTransportForTests,
+} from '../../src/core/ai/gateway.ts';
+
+afterEach(() => {
+  __setRerankTransportForTests(null);
+  resetGateway();
+});
+
+describe('recipe: litellm reranker touchpoint', () => {
+  test('declares reranker touchpoint with leaf /rerank path', () => {
+    const r = getRecipe('litellm')!;
+    const tp = r.touchpoints.reranker;
+    expect(tp).toBeDefined();
+    expect(tp!.path).toBe('/rerank');
+    expect(tp!.max_payload_bytes).toBe(5_000_000);
+  });
+
+  test('reranker touchpoint uses empty models[] for user-provided model ids', () => {
+    const r = getRecipe('litellm')!;
+    expect(r.touchpoints.reranker!.models).toEqual([]);
+  });
+
+  test('pricing stays undefined — proxy can front a paid provider', () => {
+    const r = getRecipe('litellm')!;
+    expect(r.touchpoints.reranker!.cost_per_1m_tokens_usd).toBeUndefined();
+  });
+
+  test('setup_hint keeps the /v1-suffix guidance AND mentions rerank', () => {
+    const r = getRecipe('litellm')!;
+    expect(r.setup_hint).toMatch(/\/v1 suffix/);
+    expect(r.setup_hint).toMatch(/search\.reranker\.model litellm:/);
+  });
+});
+
+describe('gateway.rerank() URL via litellm recipe', () => {
+  async function capturedRerankUrl(baseUrl?: string): Promise<string> {
+    configureGateway({
+      reranker_model: 'litellm:my-reranker',
+      env: {},
+      ...(baseUrl ? { base_urls: { litellm: baseUrl } } : {}),
+    });
+    let capturedUrl = '';
+    __setRerankTransportForTests(async (url) => {
+      capturedUrl = url;
+      return new Response(
+        JSON.stringify({ results: [{ index: 0, relevance_score: 0.9 }] }),
+        { status: 200, headers: { 'content-type': 'application/json' } },
+      );
+    });
+    await rerank({ query: 'q', documents: ['d'] });
+    return capturedUrl;
+  }
+
+  test('default base (no /v1 suffix) → /rerank', async () => {
+    const url = await capturedRerankUrl();
+    expect(url).toBe('http://localhost:4000/rerank');
+  });
+
+  test('/v1-suffixed base → /v1/rerank, NOT /v1/v1/rerank', async () => {
+    const url = await capturedRerankUrl('http://localhost:4000/v1');
+    expect(url).toBe('http://localhost:4000/v1/rerank');
+    expect(url).not.toContain('/v1/v1/');
+  });
+});

test/engine-find-trajectory.test.ts

@@ -165,22 +165,6 @@ describe('findTrajectory — visibility filter (D-CDX-1 / R6)', () => {
     const all = await engine.findTrajectory({ entitySlug: 'traj-vis-default' });
     expect(all.length).toBe(2);
   });
-
-  test('remote=true + trustedFactReads bypasses world-only (owner-trusted reads)', async () => {
-    await insertTyped({ entity_slug: 'traj-vis-trusted', metric: 'mrr', value: 50000, visibility: 'private', valid_from: new Date('2026-01-15') });
-    await insertTyped({ entity_slug: 'traj-vis-trusted', metric: 'mrr', value: 99999, visibility: 'world',   valid_from: new Date('2026-04-12') });
-
-    // Untrusted remote: world only.
-    const untrusted = await engine.findTrajectory({ entitySlug: 'traj-vis-trusted', remote: true });
-    expect(untrusted.length).toBe(1);
-    expect(untrusted[0].value).toBe(99999);
-
-    // Owner-trusted remote: sees the private point too. remote stays true — only
-    // fact-read visibility is elevated.
-    const trusted = await engine.findTrajectory({ entitySlug: 'traj-vis-trusted', remote: true, trustedFactReads: true });
-    expect(trusted.length).toBe(2);
-    expect(trusted.map(p => p.value).sort((a, b) => (a! - b!))).toEqual([50000, 99999]);
-  });
 });
 
 describe('findTrajectory — metric + since + until filters', () => {

test/facts-reader-trust.test.ts

@@ -1,43 +0,0 @@
-import { describe, test, expect } from 'bun:test';
-import {
-  factsWorldOnly,
-  readableFactVisibilities,
-} from '../src/core/facts/reader-trust.ts';
-
-describe('factsWorldOnly', () => {
-  test('FAIL-CLOSED: unset remote is untrusted (world-only)', () => {
-    expect(factsWorldOnly({})).toBe(true);
-    expect(factsWorldOnly({ remote: undefined })).toBe(true);
-    expect(factsWorldOnly({ trustedFactReads: false })).toBe(true);
-  });
-
-  test('explicit remote=false (trusted local CLI) sees all', () => {
-    expect(factsWorldOnly({ remote: false })).toBe(false);
-    expect(factsWorldOnly({ remote: false, trustedFactReads: false })).toBe(false);
-  });
-
-  test('untrusted remote callers are world-only', () => {
-    expect(factsWorldOnly({ remote: true })).toBe(true);
-    expect(factsWorldOnly({ remote: true, trustedFactReads: false })).toBe(true);
-  });
-
-  test('owner-trusted remote reads bypass the world-only filter', () => {
-    expect(factsWorldOnly({ remote: true, trustedFactReads: true })).toBe(false);
-  });
-
-  test('trustedFactReads is a no-op for an already-trusted local caller', () => {
-    expect(factsWorldOnly({ remote: false, trustedFactReads: true })).toBe(false);
-  });
-});
-
-describe('readableFactVisibilities', () => {
-  test("world-only readers get the ['world'] filter (incl. unset remote)", () => {
-    expect(readableFactVisibilities({ remote: true })).toEqual(['world']);
-    expect(readableFactVisibilities({})).toEqual(['world']);
-  });
-
-  test('trusted readers get undefined (no filter — all rows)', () => {
-    expect(readableFactVisibilities({ remote: false })).toBeUndefined();
-    expect(readableFactVisibilities({ remote: true, trustedFactReads: true })).toBeUndefined();
-  });
-});