fix(facts): fold visibility tier into hot-memory meta cache key

trustedFactReads is re-read from config on every stdio tool call, so the
reader's visibility tier can now flip within one server process. The
meta-hook cache key (source, session, allow-list hash) didn't capture it,
so a mid-session opt-out of facts.trust_local_reads could keep serving a
private-inclusive cached payload for the 30s TTL. Compute the visibility
filter before the cache lookup and append the tier to the key, restoring
the header's cross-tier no-bleed invariant.

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

src/commands/migrate-engine.ts

@@ -3,11 +3,7 @@
  *
  * Usage:
  *   gbrain migrate --to supabase [--url <connection_string>]
- *     (--url is persisted to config.json, mode 0600, so the migrated brain
- *      works without env — #1271)
  *   gbrain migrate --to pglite [--path <db_path>]
- *     (an explicit --path destination is bootstrapped with its own
- *      <path>/.gbrain/config.json so GBRAIN_HOME=<path> just works — #1271)
  *   gbrain migrate --to <engine> --force  (overwrite non-empty target)
  */
 
@@ -15,9 +11,9 @@ import { createEngine } from '../core/engine-factory.ts';
 import { loadConfig, saveConfig, toEngineConfig, gbrainPath, effectiveEnvDatabaseUrl, type GBrainConfig } from '../core/config.ts';
 import type { BrainEngine } from '../core/engine.ts';
 import type { EngineConfig } from '../core/types.ts';
-import { writeFileSync, readFileSync, existsSync, unlinkSync, mkdirSync, chmodSync } from 'fs';
+import { writeFileSync, readFileSync, existsSync, unlinkSync } from 'fs';
 import { createHash } from 'crypto';
-import { resolve, join } from 'path';
+import { resolve } from 'path';
 import { createProgress } from '../core/progress.ts';
 import { getCliOptions, cliOptsToProgressOptions } from '../core/cli-options.ts';
 
@@ -63,31 +59,6 @@ export interface MigrateManifest {
   started_at: string;
 }
 
-/**
- * #1271 Finding 1: make an explicit `--to pglite --path P` destination usable
- * as a standalone brain. Writes `P/.gbrain/config.json` (mode 0600, plus a
- * `*` .gitignore) so `GBRAIN_HOME=P` resolves without a manual `gbrain init`.
- * Never clobbers an existing config at the destination. Returns the written
- * config path, or null when skipped.
- */
-export function bootstrapDestinationConfig(dbPath: string): string | null {
-  const abs = resolve(dbPath);
-  const dir = join(abs, '.gbrain');
-  const file = join(dir, 'config.json');
-  if (existsSync(file)) return null;
-  mkdirSync(dir, { recursive: true });
-  const cfg: GBrainConfig = { engine: 'pglite', database_path: abs };
-  writeFileSync(file, JSON.stringify(cfg, null, 2) + '\n', { mode: 0o600 });
-  try { chmodSync(file, 0o600); } catch { /* platform-specific */ }
-  // Same worktree-safety pattern as saveConfig()'s ensureGitignore, scoped
-  // to the destination home. Don't clobber a user-customized .gitignore.
-  const gitignore = join(dir, '.gitignore');
-  if (!existsSync(gitignore)) {
-    writeFileSync(gitignore, '*\n', { mode: 0o600 });
-  }
-  return file;
-}
-
 export function migrationTargetId(config: EngineConfig): string {
   const locator = config.engine === 'postgres'
     ? config.database_url ?? ''
@@ -381,25 +352,6 @@ export async function runMigrateEngine(sourceEngine: BrainEngine, args: string[]
   };
   saveConfig(newConfig);
 
-  // #1271 Finding 2 (by design, but say it out loud): the connection string
-  // is persisted so the migrated brain works without env. Mode 0600.
-  if (opts.targetEngine === 'postgres' && opts.targetUrl) {
-    console.error('Note: the --url connection string (including credentials) is persisted to config.json (mode 0600).');
-  }
-
-  // #1271 Finding 1: an explicit --path destination doubles as a standalone
-  // GBRAIN_HOME. Best-effort — never fail a completed migration over it.
-  if (opts.targetEngine === 'pglite' && opts.targetPath) {
-    try {
-      const written = bootstrapDestinationConfig(opts.targetPath);
-      if (written) {
-        console.log(`Destination bootstrapped: ${written} (usable via GBRAIN_HOME=${resolve(opts.targetPath)})`);
-      }
-    } catch (e) {
-      console.warn(`  WARN could not bootstrap destination config: ${e instanceof Error ? e.message : String(e)}`);
-    }
-  }
-
   // Clean up
   clearManifest();
 

src/core/config.ts

@@ -908,6 +908,10 @@ 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

@@ -591,6 +591,8 @@ 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

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

@@ -0,0 +1,48 @@
+/**
+ * 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

@@ -18,6 +18,7 @@ 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';
@@ -332,6 +333,15 @@ 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
@@ -3629,6 +3639,7 @@ const find_trajectory: Operation = {
       entitySlug: p.entity_slug,
       ...scope,
       remote: ctx.remote === true,
+      trustedFactReads: ctx.trustedFactReads === true,
       metric,
       kind,
       since,
@@ -3989,13 +4000,9 @@ const recall: Operation = {
     const includeExpired = p.include_expired === true;
     const grep = typeof p.grep === 'string' ? p.grep.toLowerCase() : null;
 
-    // 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')[];
+    // 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);
 
     let rows: Awaited<ReturnType<typeof ctx.engine.listFactsByEntity>> = [];
 

src/core/pglite-engine.ts

@@ -18,6 +18,7 @@ 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';
@@ -4318,7 +4319,10 @@ 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';
-    const remoteFilter = opts.remote === true;
+    // 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 });
 
     // 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

@@ -14,6 +14,7 @@ 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,
@@ -4532,7 +4533,10 @@ 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';
-    const remoteFilter = opts.remote === true;
+    // 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 });
 
     // Source-scope predicate: array path (federated) wins over scalar.
     // Engine.ts contract: returns chronological points; regressions +

src/mcp/dispatch.ts

@@ -30,6 +30,13 @@ 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'];
   /**
@@ -203,6 +210,7 @@ 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

@@ -35,6 +35,16 @@ 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
@@ -42,6 +52,7 @@ 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/engine-find-trajectory.test.ts

@@ -165,6 +165,22 @@ 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

@@ -0,0 +1,43 @@
+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();
+  });
+});

test/migrate-engine-dest-bootstrap.test.ts

@@ -1,40 +0,0 @@
-import { describe, expect, test } from 'bun:test';
-import { mkdtempSync, mkdirSync, readFileSync, statSync, writeFileSync } from 'fs';
-import { tmpdir } from 'os';
-import { join, resolve } from 'path';
-import { bootstrapDestinationConfig } from '../src/commands/migrate-engine.ts';
-import { loadConfigFileOnly } from '../src/core/config.ts';
-import { withEnv } from './helpers/with-env.ts';
-
-describe('migrate --to pglite destination bootstrap (#1271)', () => {
-  test('writes <path>/.gbrain/config.json so GBRAIN_HOME=<path> resolves a brain', async () => {
-    const dest = mkdtempSync(join(tmpdir(), 'gbrain-dest-'));
-    const written = bootstrapDestinationConfig(dest);
-    const file = join(dest, '.gbrain', 'config.json');
-    expect(written).toBe(file);
-
-    const cfg = JSON.parse(readFileSync(file, 'utf-8'));
-    expect(cfg.engine).toBe('pglite');
-    expect(cfg.database_path).toBe(resolve(dest));
-    expect(statSync(file).mode & 0o777).toBe(0o600);
-    // worktree safety: destination home is git-ignored like saveConfig()'s home
-    expect(readFileSync(join(dest, '.gbrain', '.gitignore'), 'utf-8')).toBe('*\n');
-
-    // The exact failure mode from #1271: config resolution under
-    // GBRAIN_HOME=<path> used to find nothing ("No brain configured").
-    await withEnv({ GBRAIN_HOME: dest }, () => {
-      const loaded = loadConfigFileOnly();
-      expect(loaded?.engine).toBe('pglite');
-      expect(loaded?.database_path).toBe(resolve(dest));
-    });
-  });
-
-  test('never clobbers an existing destination config', () => {
-    const dest = mkdtempSync(join(tmpdir(), 'gbrain-dest-'));
-    mkdirSync(join(dest, '.gbrain'), { recursive: true });
-    writeFileSync(join(dest, '.gbrain', 'config.json'), '{"engine":"postgres"}\n');
-
-    expect(bootstrapDestinationConfig(dest)).toBe(null);
-    expect(JSON.parse(readFileSync(join(dest, '.gbrain', 'config.json'), 'utf-8')).engine).toBe('postgres');
-  });
-});