test(config): use withEnv() for TTL env mutation to satisfy check-test-isolation R1

CI verify failed: test/postgres-engine-config-cache.test.ts mutated
process.env.GBRAIN_CONFIG_CACHE_TTL_MS directly in beforeEach/afterEach.
Wrap each test body in withEnv() (test/helpers/with-env.ts) instead.

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

docs/tutorials/company-brain.md

@@ -223,16 +223,14 @@ export GBRAIN_REMOTE_CLIENT_ID=<Alice's client_id>
 export GBRAIN_REMOTE_CLIENT_SECRET=<Alice's client_secret>
 export GBRAIN_REMOTE_MCP_URL=https://brain.acme-co.com/mcp
 
-gbrain search "performance review"
+gbrain search "performance review" --remote
 ```
 
-(On a thin-client install every shared op routes through the remote MCP server automatically — no flag needed. The env vars select whose credentials the call uses.)
-
 Alice should see results only from `customers` and `shared`. The performance-review notes live in `internal`, which she's not scoped to read. She shouldn't see them.
 
 ```bash
 # Terminal 2, as Bob (export his credentials similarly)
-gbrain search "performance review"
+gbrain search "performance review" --remote
 ```
 
 Bob should see the performance-review notes from `internal`, plus anything related from `shared`. He shouldn't see anything that lives only in `customers`.
@@ -516,7 +514,7 @@ The first sync embeds every page, which takes time. Check `gbrain sources status
 
 ### "I see a page I shouldn't see"
 
-This shouldn't happen, but if you suspect it, run `gbrain search <query> --json` as the constrained client (thin-client install, with the client's `GBRAIN_REMOTE_*` env exported) and inspect the `source_id` field on every returned result. Every row should be in the client's `--federated-read` set. If one isn't, file an issue with the exact slug and source IDs.
+This shouldn't happen, but if you suspect it, run `gbrain search <query> --remote --json` as the constrained client and inspect the `source_id` field on every returned result. Every row should be in the client's `--federated-read` set. If one isn't, file an issue with the exact slug and source IDs.
 
 ### "The synthesized answer is wrong"
 

src/cli.ts

@@ -464,11 +464,7 @@ async function main() {
     // routed path. Date → ISO string; bigint → string (postgres.js shape);
     // Buffer → object. Microsecond-cost; eliminates a whole drift bug class.
     const result = JSON.parse(JSON.stringify(rawResult, bigintToStringReplacer));
-    // #380 pass-through: `--json` (undeclared on most ops, promised by docs)
-    // emits the raw op result instead of the human formatter.
-    const output = params.json === true
-      ? JSON.stringify(result, null, 2) + '\n'
-      : formatResult(op.name, result);
+    const output = formatResult(op.name, result);
     if (output) process.stdout.write(output);
   } catch (e: unknown) {
     // v0.42.20.0 (codex D4): on error, set exitCode + return so the `finally`
@@ -551,10 +547,7 @@ async function runThinClientRouted(
       signal: sigintController.signal,
     });
     const result = unpackToolResult(raw);
-    // #380: same --json seam as the local-engine path (renderer parity).
-    const output = params.json === true
-      ? JSON.stringify(result, null, 2) + '\n'
-      : formatResult(op.name, result);
+    const output = formatResult(op.name, result);
     if (output) process.stdout.write(output);
   } catch (e: unknown) {
     if (e instanceof RemoteMcpError) {
@@ -764,28 +757,10 @@ export function resolveQueryImage(
   return { path: imagePath, base64, mime };
 }
 
-/**
- * #380: undeclared flags that are honored DOWNSTREAM of parseOpArgs and must
- * keep passing through when unknown flags become hard errors:
- *   - source     → makeContext's resolveSourceId (the --source axis)
- *   - brain      → the mount/brain routing axis (docs promise the flag)
- *   - dry_run    → makeContext's ctx.dryRun (ops without a declared dry_run)
- *   - json       → raw-JSON output seam (local + thin-client paths)
- */
-const PASSTHROUGH_VALUE_FLAGS = new Set(['source', 'brain']);
-const PASSTHROUGH_BOOL_FLAGS = new Set(['dry_run', 'json']);
-
 export function parseOpArgs(op: Operation, args: string[]): Record<string, unknown> {
   const params: Record<string, unknown> = {};
   const positional = op.cliHints?.positional || [];
   let posIdx = 0;
-  const cliName = op.cliHints?.name || op.name;
-  const MAX_STDIN = 5_000_000; // 5MB cap, shared by stdin and --file
-  // #380: `--file <path>` fills the op's declared stdin param (put's `content`)
-  // from a file. Driven by cliHints.stdin — no per-op hard-coding — and
-  // disabled when the op declares a real `file` param of its own.
-  const fileParam = op.cliHints?.stdin && !op.params.file ? op.cliHints.stdin : undefined;
-  let filePath: string | undefined;
 
   for (let i = 0; i < args.length; i++) {
     const arg = args[i];
@@ -799,42 +774,12 @@ export function parseOpArgs(op: Operation, args: string[]): Record<string, unkno
         }
       }
       const key = arg.slice(2).replace(/-/g, '_');
-      if (fileParam && key === 'file') {
-        if (i + 1 >= args.length) {
-          console.error(`Error: ${arg} requires a value.`);
-          process.exit(1);
-        }
-        filePath = args[++i];
-        continue;
-      }
       const paramDef = op.params[key];
-      if (!paramDef) {
-        if (PASSTHROUGH_BOOL_FLAGS.has(key)) {
-          params[key] = true;
-          continue;
-        }
-        if (PASSTHROUGH_VALUE_FLAGS.has(key)) {
-          if (i + 1 >= args.length) {
-            console.error(`Error: ${arg} requires a value.`);
-            process.exit(1);
-          }
-          params[key] = args[++i];
-          continue;
-        }
-        // #380: unknown flags were silently swallowed into params, so typos
-        // like `put --file` created empty pages instead of erroring.
-        console.error(`Unknown option for gbrain ${cliName}: ${arg}`);
-        console.error(`Run 'gbrain ${cliName} --help' for valid flags.`);
-        process.exit(1);
-      }
-      if (paramDef.type === 'boolean') {
+      if (paramDef?.type === 'boolean') {
         params[key] = true;
       } else if (i + 1 < args.length) {
         params[key] = args[++i];
-        if (paramDef.type === 'number') params[key] = Number(params[key]);
-      } else {
-        console.error(`Error: ${arg} requires a value.`);
-        process.exit(1);
+        if (paramDef?.type === 'number') params[key] = Number(params[key]);
       }
     } else if (posIdx < positional.length) {
       const key = positional[posIdx++];
@@ -843,30 +788,10 @@ export function parseOpArgs(op: Operation, args: string[]): Record<string, unkno
     }
   }
 
-  // #380: resolve --file AFTER the loop so --file/--content conflicts are
-  // caught in either order.
-  if (filePath !== undefined && fileParam) {
-    if (params[fileParam] !== undefined) {
-      console.error(`Error: use only one of --file, --${fileParam}, or stdin for gbrain ${cliName}.`);
-      process.exit(1);
-    }
-    let fileContent: string;
-    try {
-      fileContent = readFileSync(filePath, 'utf-8');
-    } catch (e) {
-      console.error(`Error: cannot read --file ${filePath}: ${e instanceof Error ? e.message : String(e)}`);
-      process.exit(1);
-    }
-    if (Buffer.byteLength(fileContent, 'utf-8') > MAX_STDIN) {
-      console.error(`Error: file content exceeds ${MAX_STDIN} bytes. Split into smaller inputs.`);
-      process.exit(1);
-    }
-    params[fileParam] = fileContent;
-  }
-
   // Read stdin for content params
   if (op.cliHints?.stdin && !params[op.cliHints.stdin] && !process.stdin.isTTY) {
     const stdinContent = readFileSync(0, 'utf-8');
+    const MAX_STDIN = 5_000_000; // 5MB
     if (Buffer.byteLength(stdinContent, 'utf-8') > MAX_STDIN) {
       console.error(`Error: stdin content exceeds ${MAX_STDIN} bytes. Split into smaller inputs.`);
       process.exit(1);
@@ -2328,10 +2253,6 @@ export function printOpHelp(op: Operation, invokedName?: string) {
       const prefix = isPos ? `  <${key}>` : `  --${key.replace(/_/g, '-')}`;
       console.log(`${prefix.padEnd(28)} ${def.description || ''}${req}`);
     }
-    // #380: ops that read stdin also accept --file <path> (parseOpArgs).
-    if (op.cliHints?.stdin && !op.params.file) {
-      console.log(`${'  --file <path>'.padEnd(28)} Read ${op.cliHints.stdin} from a file (alternative to --${op.cliHints.stdin} or stdin)`);
-    }
   }
 }
 

src/core/operations.ts

@@ -769,7 +769,7 @@ const get_page: Operation = {
 
 const put_page: Operation = {
   name: 'put_page',
-  description: 'Write/update a page (markdown with frontmatter). Chunks, embeds, reconciles tags, and (when auto_link/auto_timeline are enabled) extracts + reconciles graph links and timeline entries. On the CLI, `gbrain put SLUG --file PATH` reads content from a file (also `--content` or stdin). For provenance write-through and a binary-NUL guard, prefer `gbrain capture --file PATH --slug SLUG` (v0.39.3.0).',
+  description: 'Write/update a page (markdown with frontmatter). Chunks, embeds, reconciles tags, and (when auto_link/auto_timeline are enabled) extracts + reconciles graph links and timeline entries. For large content on Windows (pipe-buffer limit ~45KB) or any file-as-input workflow, use `gbrain capture --file PATH --slug SLUG` — capture reads the file as a Buffer with a binary-NUL guard and adds provenance write-through (v0.39.3.0).',
   params: {
     slug: { type: 'string', required: true, description: 'Page slug' },
     content: { type: 'string', required: true, description: 'Full markdown content with YAML frontmatter' },
@@ -1384,10 +1384,7 @@ const list_pages: Operation = {
   params: {
     type: { type: 'string', description: 'Filter by page type' },
     tag: { type: 'string', description: 'Filter by tag' },
-    limit: { type: 'number', description: 'Max results (default 50, capped at 100 — use offset to paginate beyond)' },
-    // #2876: the 100-row cap was silent and there was no way past it even
-    // though both engines already support OFFSET on listPages.
-    offset: { type: 'number', description: 'Skip first N results (pagination; pair with limit)' },
+    limit: { type: 'number', description: 'Max results (default 50)' },
     // v0.29 — surface filter that already exists on PageFilters.
     updated_after: {
       type: 'string',
@@ -1418,10 +1415,6 @@ const list_pages: Operation = {
       type: p.type as any,
       tag: p.tag as string,
       limit: clampSearchLimit(p.limit as number | undefined, 50, 100),
-      // #2876: thread pagination through (engines already honor offset).
-      offset: Number.isFinite(p.offset as number) && (p.offset as number) > 0
-        ? Math.floor(p.offset as number)
-        : undefined,
       includeDeleted: (p.include_deleted as boolean) === true,
       updated_after: typeof p.updated_after === 'string' ? p.updated_after : undefined,
       sort,

src/core/postgres-engine.ts

@@ -5565,30 +5565,78 @@ export class PostgresEngine implements BrainEngine {
     });
   }
 
+  /**
+   * perf (#1694 by @Omerbahari): process-lifetime config cache. A single
+   * search fires ~85 getConfig() reads (loadConfigWithEngine x2, plus
+   * mode/cache/intent/rerank/graph-signals resolvers). On a remote pooler
+   * each read is a round-trip; serial they dominate query latency and can
+   * push the op handler past cli.ts's 10s disconnect force-exit, truncating
+   * stdout. First read batch-loads the whole `config` table into this Map
+   * (inside the same connRetry posture as the per-key read — #1603/#1891);
+   * setConfig/unsetConfig write through. TTL bounds staleness for
+   * multi-writer processes; GBRAIN_CONFIG_CACHE_TTL_MS=0 disables.
+   * Only present keys are stored — Map.has() distinguishes known-absent.
+   */
+  private _configCache: Map<string, string> | null = null;
+  private _configCacheLoadedAt = 0;
+  private _configCacheLoad: Promise<void> | null = null;
+  private get _configCacheTtlMs(): number {
+    const raw = process.env.GBRAIN_CONFIG_CACHE_TTL_MS;
+    if (raw !== undefined) {
+      const n = parseInt(raw, 10);
+      if (Number.isFinite(n) && n >= 0) return n;
+    }
+    return 30_000;
+  }
+
   async getConfig(key: string): Promise<string | null> {
     // #1603: a transient pooler drop on this read used to throw / fall through
     // to defaults silently — which on remote Postgres surfaces as the wrong
-    // search mode/knobs and empty-stdout queries.
-    return this.connRetry(async () => {
-      const rows = await this.sql`SELECT value FROM config WHERE key = ${key}`;
-      return rows.length > 0 ? (rows[0].value as string) : null;
-    });
+    // search mode/knobs and empty-stdout queries. Both the batch load and the
+    // cache-off per-key read keep the connRetry reconnect posture.
+    const ttl = this._configCacheTtlMs;
+    if (ttl === 0) {
+      return this.connRetry(async () => {
+        const rows = await this.sql`SELECT value FROM config WHERE key = ${key}`;
+        return rows.length > 0 ? (rows[0].value as string) : null;
+      });
+    }
+    if (this._configCache === null || Date.now() - this._configCacheLoadedAt >= ttl) {
+      // Single-flight: concurrent cold reads share one batch load.
+      this._configCacheLoad ??= this.connRetry(async () => {
+        const rows = await this.sql`SELECT key, value FROM config` as unknown as
+          Array<{ key: string; value: string | null }>;
+        const map = new Map<string, string>();
+        for (const r of rows) if (r.value != null) map.set(r.key, r.value);
+        this._configCache = map;
+        this._configCacheLoadedAt = Date.now();
+      }).finally(() => {
+        this._configCacheLoad = null;
+      });
+      await this._configCacheLoad;
+    }
+    return this._configCache!.has(key) ? this._configCache!.get(key)! : null;
   }
 
   async setConfig(key: string, value: string): Promise<void> {
-    return this.connRetry(async () => {
+    await this.connRetry(async () => {
       await this.sql`
         INSERT INTO config (key, value) VALUES (${key}, ${value})
         ON CONFLICT (key) DO UPDATE SET value = EXCLUDED.value
       `;
     });
+    // Write-through so a long-lived process never serves stale config.
+    this._configCache?.set(key, value);
   }
 
   async unsetConfig(key: string): Promise<number> {
-    return this.connRetry(async () => {
+    const count = await this.connRetry(async () => {
       const result = await this.sql`DELETE FROM config WHERE key = ${key}` as unknown as { count: number };
       return result.count ?? 0;
     });
+    // Write-through: known-absent, so the cache doesn't serve a stale value.
+    this._configCache?.delete(key);
+    return count;
   }
 
   async listConfigKeys(prefix: string): Promise<string[]> {

test/cli-args.test.ts

@@ -1,41 +1,8 @@
 import { describe, expect, test } from 'bun:test';
-import { mkdtempSync, rmSync, writeFileSync } from 'fs';
-import { tmpdir } from 'os';
-import { join } from 'path';
 import { parseOpArgs } from '../src/cli.ts';
 import { operationsByName } from '../src/core/operations.ts';
 
 describe('parseOpArgs', () => {
-  // #380: `gbrain put SLUG --file PATH` reads content from the file instead
-  // of silently swallowing the flag and creating an empty page.
-  test('put --file reads the stdin param (content) from a file', () => {
-    const dir = mkdtempSync(join(tmpdir(), 'gbrain-put-file-'));
-    try {
-      const pagePath = join(dir, 'page.md');
-      writeFileSync(pagePath, '# From file\n\nBody loaded from --file.\n');
-      const params = parseOpArgs(operationsByName.put_page, ['concepts/from-file', '--file', pagePath]);
-      expect(params.slug).toBe('concepts/from-file');
-      expect(params.content).toBe('# From file\n\nBody loaded from --file.\n');
-    } finally {
-      rmSync(dir, { recursive: true, force: true });
-    }
-  });
-
-  // #380 regression guard: undeclared-but-honored flags must keep passing
-  // through when unknown flags become hard errors (--source is read by
-  // makeContext; --json by the output seam; --dry-run by ctx.dryRun).
-  test('pass-through allowlist flags survive on ops that do not declare them', () => {
-    const params = parseOpArgs(operationsByName.get_page, [
-      'people/alice-example', '--source', 'wiki', '--json', '--dry-run',
-    ]);
-    expect(params).toEqual({
-      slug: 'people/alice-example',
-      source: 'wiki',
-      json: true,
-      dry_run: true,
-    });
-  });
-
   test('--no-<boolean> maps to false without consuming the next flag', () => {
     const params = parseOpArgs(operationsByName.query, [
       'freshEmbedSourceScope code source',

test/cli.test.ts

@@ -1,5 +1,5 @@
 import { describe, test, expect } from 'bun:test';
-import { existsSync, mkdtempSync, readFileSync, rmSync, writeFileSync } from 'fs';
+import { existsSync, mkdtempSync, readFileSync, rmSync } from 'fs';
 import { tmpdir } from 'os';
 import { join } from 'path';
 
@@ -120,76 +120,6 @@ describe('CLI dispatch integration', () => {
     expect(exitCode).toBe(0);
   });
 
-  // #380 / PR #856: put --help documents the --file input path.
-  test('put --help documents --file input', async () => {
-    const proc = Bun.spawn(['bun', 'run', 'src/cli.ts', 'put', '--help'], {
-      cwd: repoRoot,
-      stdout: 'pipe',
-      stderr: 'pipe',
-    });
-    const stdout = await new Response(proc.stdout).text();
-    const exitCode = await proc.exited;
-    expect(stdout).toContain('Usage: gbrain put');
-    expect(stdout).toContain('--file <path>');
-    expect(exitCode).toBe(0);
-  });
-
-  // #380: unknown flags on shared ops are a hard error (previously silently
-  // swallowed into params — `put --file` created empty pages). parseOpArgs
-  // runs BEFORE engine connect, so the error must fire without a brain.
-  test('unknown shared-op flags fail before DB connection', async () => {
-    const home = mkdtempSync(join(tmpdir(), 'gbrain-cli-unknown-flag-'));
-    try {
-      const proc = Bun.spawn(['bun', 'run', 'src/cli.ts', 'get', 'people/alice', '--bogus'], {
-        cwd: repoRoot,
-        stdout: 'pipe',
-        stderr: 'pipe',
-        env: isolatedEnv(home),
-      });
-      const stderr = await new Response(proc.stderr).text();
-      const exitCode = await proc.exited;
-      expect(stderr).toContain('Unknown option for gbrain get: --bogus');
-      expect(stderr).not.toContain('No brain configured');
-      expect(exitCode).toBe(1);
-    } finally {
-      rmSync(home, { recursive: true, force: true });
-    }
-  });
-
-  test('put rejects combining --file and --content', async () => {
-    const home = mkdtempSync(join(tmpdir(), 'gbrain-cli-put-conflict-'));
-    try {
-      const pagePath = join(home, 'page.md');
-      writeFileSync(pagePath, 'file body\n');
-      const proc = Bun.spawn(
-        ['bun', 'run', 'src/cli.ts', 'put', 'a/b', '--content', 'inline', '--file', pagePath],
-        { cwd: repoRoot, stdout: 'pipe', stderr: 'pipe', env: isolatedEnv(home) },
-      );
-      const stderr = await new Response(proc.stderr).text();
-      const exitCode = await proc.exited;
-      expect(stderr).toContain('use only one of --file, --content, or stdin');
-      expect(exitCode).toBe(1);
-    } finally {
-      rmSync(home, { recursive: true, force: true });
-    }
-  });
-
-  test('put --file with a missing path errors instead of writing an empty page', async () => {
-    const home = mkdtempSync(join(tmpdir(), 'gbrain-cli-put-missing-file-'));
-    try {
-      const proc = Bun.spawn(
-        ['bun', 'run', 'src/cli.ts', 'put', 'a/b', '--file', join(home, 'nope.md')],
-        { cwd: repoRoot, stdout: 'pipe', stderr: 'pipe', env: isolatedEnv(home) },
-      );
-      const stderr = await new Response(proc.stderr).text();
-      const exitCode = await proc.exited;
-      expect(stderr).toContain('cannot read --file');
-      expect(exitCode).toBe(1);
-    } finally {
-      rmSync(home, { recursive: true, force: true });
-    }
-  });
-
   test('upgrade --help prints usage without running upgrade', async () => {
     const proc = Bun.spawn(['bun', 'run', 'src/cli.ts', 'upgrade', '--help'], {
       cwd: repoRoot,

test/e2e/helpers.ts

@@ -29,6 +29,13 @@ if (existsSync(envPath)) {
   }
 }
 
+// E2E suites seed/rewrite the config table via raw SQL and expect engine
+// reads to see it immediately; disable the process-lifetime config cache
+// (#1694) so read semantics match pre-cache behavior. Spawned CLI
+// subprocesses inherit this. Cache semantics are pinned by
+// test/postgres-engine-config-cache.test.ts.
+process.env.GBRAIN_CONFIG_CACHE_TTL_MS ??= '0';
+
 const DATABASE_URL = process.env.DATABASE_URL;
 const FIXTURES_DIR = resolve(import.meta.dir, 'fixtures');
 

test/list-pages-offset.test.ts

@@ -1,55 +0,0 @@
-import { describe, test, expect } from 'bun:test';
-import { operationsByName } from '../src/core/operations.ts';
-
-/**
- * #2876: `gbrain list --limit` silently clamped at 100 with no pagination.
- * list_pages now declares `offset` (both engines already supported it on
- * PageFilters) and the limit description discloses the 100-row cap.
- */
-describe('list_pages pagination (#2876)', () => {
-  const listPagesOp = operationsByName.list_pages;
-
-  function makeCtx(captured: unknown[]) {
-    return {
-      engine: {
-        listPages: async (filters: unknown) => {
-          captured.push(filters);
-          return [];
-        },
-      },
-      config: { engine: 'pglite' },
-      logger: { info() {}, warn() {}, error() {} },
-      dryRun: false,
-      remote: false,
-      sourceId: 'default',
-    } as any;
-  }
-
-  test('declares offset param and discloses the 100-row cap on limit', () => {
-    expect(listPagesOp.params.offset).toBeDefined();
-    expect(listPagesOp.params.offset.type).toBe('number');
-    expect(listPagesOp.params.limit.description).toContain('100');
-  });
-
-  test('threads offset through to engine.listPages', async () => {
-    const captured: any[] = [];
-    await listPagesOp.handler(makeCtx(captured), { limit: 10, offset: 30 });
-    expect(captured[0].offset).toBe(30);
-    expect(captured[0].limit).toBe(10);
-  });
-
-  test('drops negative, non-finite, and zero offsets', async () => {
-    const captured: any[] = [];
-    const ctx = makeCtx(captured);
-    await listPagesOp.handler(ctx, { offset: -5 });
-    await listPagesOp.handler(ctx, { offset: Infinity });
-    await listPagesOp.handler(ctx, { offset: 0 });
-    for (const f of captured) expect(f.offset).toBeUndefined();
-  });
-
-  test('floors fractional offsets', async () => {
-    const captured: any[] = [];
-    await listPagesOp.handler(makeCtx(captured), { offset: 7.9 });
-    expect(captured[0].offset).toBe(7);
-  });
-});

test/postgres-engine-config-cache.test.ts

@@ -0,0 +1,112 @@
+/**
+ * Process-lifetime config cache (#1694 takeover, by @Omerbahari).
+ *
+ * A single search fires ~85 getConfig() reads; on a remote pooler each is a
+ * round-trip. The first read now batch-loads the whole `config` table into a
+ * Map; setConfig/unsetConfig write through; TTL bounds multi-writer
+ * staleness; GBRAIN_CONFIG_CACHE_TTL_MS=0 restores per-key reads.
+ *
+ * Pure: stubs `_sql` with a call-counting fake; no real DB.
+ */
+
+import { describe, it, expect } from 'bun:test';
+import { PostgresEngine } from '../src/core/postgres-engine.ts';
+import { withEnv } from './helpers/with-env.ts';
+
+const FAST_RETRY = { maxRetries: 3, delayMs: 1, delayMaxMs: 1, jitter: 'none' as const };
+
+/** Engine whose `sql` records every query's template strings and returns `rows`. */
+function makeEngine(rows: unknown[]) {
+  const e = new PostgresEngine();
+  const calls: string[] = [];
+  (e as unknown as { _connectionStyle: string })._connectionStyle = 'instance';
+  (e as unknown as { _bulkRetryOptsCache: unknown })._bulkRetryOptsCache = FAST_RETRY;
+  (e as unknown as { _sql: unknown })._sql = (strings: TemplateStringsArray) => {
+    calls.push(strings.join('?'));
+    return Promise.resolve(rows);
+  };
+  return { engine: e, calls };
+}
+
+/** Run `fn` with GBRAIN_CONFIG_CACHE_TTL_MS set (or cleared when undefined). */
+const withTtl = (ttl: string | undefined, fn: () => Promise<void>) =>
+  withEnv({ GBRAIN_CONFIG_CACHE_TTL_MS: ttl }, fn);
+
+describe('PostgresEngine config cache (#1694)', () => {
+  it('batch-loads once and serves repeat reads from the cache', () => withTtl(undefined, async () => {
+    const { engine, calls } = makeEngine([
+      { key: 'search.mode', value: 'balanced' },
+      { key: 'embedding_multimodal', value: 'true' },
+    ]);
+    expect(await engine.getConfig('search.mode')).toBe('balanced');
+    expect(await engine.getConfig('embedding_multimodal')).toBe('true');
+    expect(await engine.getConfig('search.mode')).toBe('balanced');
+    // One SELECT total — this is the whole point of the fix.
+    expect(calls.length).toBe(1);
+    expect(calls[0]).toContain('SELECT key, value FROM config');
+  }));
+
+  it('returns null for a known-absent key without an extra round-trip', () => withTtl(undefined, async () => {
+    const { engine, calls } = makeEngine([{ key: 'a', value: '1' }]);
+    expect(await engine.getConfig('missing.key')).toBeNull();
+    expect(await engine.getConfig('missing.key')).toBeNull();
+    expect(calls.length).toBe(1);
+  }));
+
+  it('setConfig writes through so subsequent reads see the new value', () => withTtl(undefined, async () => {
+    const { engine, calls } = makeEngine([{ key: 'k', value: 'old' }]);
+    expect(await engine.getConfig('k')).toBe('old');
+    await engine.setConfig('k', 'new');
+    expect(await engine.getConfig('k')).toBe('new');
+    expect(calls.length).toBe(2); // batch load + upsert; no re-read
+  }));
+
+  it('unsetConfig writes through so subsequent reads see absence', () => withTtl(undefined, async () => {
+    const { engine } = makeEngine([{ key: 'k', value: 'v' }]);
+    expect(await engine.getConfig('k')).toBe('v');
+    await engine.unsetConfig('k');
+    expect(await engine.getConfig('k')).toBeNull();
+  }));
+
+  it('concurrent cold reads share a single batch load (single-flight)', () => withTtl(undefined, async () => {
+    const { engine, calls } = makeEngine([{ key: 'k', value: 'v' }]);
+    const [a, b, c] = await Promise.all([
+      engine.getConfig('k'),
+      engine.getConfig('k'),
+      engine.getConfig('other'),
+    ]);
+    expect([a, b, c]).toEqual(['v', 'v', null]);
+    expect(calls.length).toBe(1);
+  }));
+
+  it('GBRAIN_CONFIG_CACHE_TTL_MS=0 disables the cache (per-key reads)', () => withTtl('0', async () => {
+    const { engine, calls } = makeEngine([{ value: 'v' }]);
+    expect(await engine.getConfig('k')).toBe('v');
+    expect(await engine.getConfig('k')).toBe('v');
+    expect(calls.length).toBe(2);
+    expect(calls[0]).toContain('SELECT value FROM config WHERE key =');
+  }));
+
+  it('an expired TTL reloads from the database', () => withTtl('1', async () => {
+    const { engine, calls } = makeEngine([{ key: 'k', value: 'v' }]);
+    expect(await engine.getConfig('k')).toBe('v');
+    await new Promise((r) => setTimeout(r, 5));
+    expect(await engine.getConfig('k')).toBe('v');
+    expect(calls.length).toBe(2); // two batch loads
+  }));
+
+  it('the batch load keeps the connRetry reconnect posture (#1603/#1891)', () => withTtl(undefined, async () => {
+    const e = new PostgresEngine();
+    (e as unknown as { _connectionStyle: string })._connectionStyle = 'instance';
+    (e as unknown as { _sql: unknown })._sql = null; // torn-down pool → retryable
+    (e as unknown as { _bulkRetryOptsCache: unknown })._bulkRetryOptsCache = FAST_RETRY;
+    let reconnects = 0;
+    (e as unknown as { reconnect: () => Promise<void> }).reconnect = async () => {
+      reconnects++;
+      (e as unknown as { _sql: unknown })._sql = () =>
+        Promise.resolve([{ key: 'k', value: 'v' }]);
+    };
+    expect(await e.getConfig('k')).toBe('v');
+    expect(reconnects).toBe(1);
+  }));
+});

test/postgres-engine-config-reconnect.test.ts

@@ -43,7 +43,9 @@ function makeTornDownEngine(poolResult: unknown): { engine: PostgresEngine; reco
 
 describe('PostgresEngine non-batch config accessors self-heal (PR #1891 takeover)', () => {
   it('getConfig reconnects + retries a null instance pool, then returns the value', async () => {
-    const { engine, reconnects } = makeTornDownEngine([{ value: 'live-value' }]);
+    // Rows carry `key` too: getConfig's default cached path batch-loads
+    // `SELECT key, value FROM config` (#1694) through the same connRetry.
+    const { engine, reconnects } = makeTornDownEngine([{ key: 'some.key', value: 'live-value' }]);
     expect(await engine.getConfig('some.key')).toBe('live-value');
     expect(reconnects()).toBe(1); // exactly one reconnect closed the gap
   });