A5: brain-sync stage fails loud when the artifacts source indexed zero pages

The stage reported "curated artifacts pushed" whenever gstack-brain-sync
exited 0, but a git push is not gbrain indexing. After a successful push
the stage now reads the maintained artifacts source's page count
(GSTACK_BRAIN_SOURCE_ID, else the source whose path is the artifacts
worktree or state root): zero pages is ERR with the fix command; a
missing source or an unavailable count says so instead of claiming
indexing.

Co-authored-by: Jimmy Zeisweiss <4261258+jzeisweiss@users.noreply.github.com>

bin/gstack-gbrain-sync.ts

@@ -214,6 +214,13 @@ export function resolveMemoryIngestSources(
  * state root itself), if any. Its pages already cover FEDERATED_CURATED_TYPES.
  */
 export function federatedCuratedSourceId(env?: NodeJS.ProcessEnv): string | null {
+  const rows = parseSourcesList(execGbrainJson(["sources", "list", "--json"], { baseEnv: env, timeout: 10_000 }));
+  const row = rows.find((r) => (r as { federated?: boolean }).federated === true && isArtifactsSourceRow(r, env));
+  return row?.id ?? null;
+}
+
+/** A source this installation maintains for its curated artifacts (the worktree or the state root). */
+function isArtifactsSourceRow(r: { local_path?: string }, env?: NodeJS.ProcessEnv): boolean {
   const realOrSelf = (p: string): string => {
     try {
       return realpathSync(p);
@@ -226,9 +233,36 @@ export function federatedCuratedSourceId(env?: NodeJS.ProcessEnv): string | null
     realOrSelf((env ?? process.env).GSTACK_BRAIN_WORKTREE || join(home, ".gstack-brain-worktree")),
     realOrSelf(GSTACK_HOME),
   ]);
-  const rows = parseSourcesList(execGbrainJson(["sources", "list", "--json"], { baseEnv: env, timeout: 10_000 }));
-  const row = rows.find((r) => (r as { federated?: boolean }).federated === true && r.local_path && owned.has(realOrSelf(r.local_path)));
-  return row?.id ?? null;
+  return !!r.local_path && owned.has(realOrSelf(r.local_path));
+}
+
+/**
+ * A5 (#2670): after a successful artifacts push, report what gbrain actually
+ * holds. A git push is not indexing; a maintained artifacts source with zero
+ * pages is the one provably broken state and fails the stage.
+ */
+export function brainSyncIndexVerdict(env: NodeJS.ProcessEnv = process.env): { ok: boolean; summary: string } {
+  const raw = execGbrainJson(["sources", "list", "--json"], { baseEnv: env, timeout: 10_000 });
+  if (raw === null) {
+    return { ok: true, summary: "curated artifacts pushed to git; gbrain page count unavailable (gbrain sources list failed)" };
+  }
+  const explicit = env.GSTACK_BRAIN_SOURCE_ID;
+  const row = parseSourcesList(raw).find((r) => (explicit ? r.id === explicit : isArtifactsSourceRow(r, env)));
+  if (!row?.id) {
+    return { ok: true, summary: "curated artifacts pushed to git (no gbrain artifacts source on this machine, so indexing is not checked here)" };
+  }
+  if (typeof row.page_count !== "number") {
+    return { ok: true, summary: `curated artifacts pushed to git; gbrain source ${row.id} did not report a page count` };
+  }
+  if (row.page_count === 0) {
+    return {
+      ok: false,
+      summary:
+        `curated artifacts pushed to git, but gbrain source ${row.id} has 0 indexed pages. ` +
+        `Fix: gbrain sync --source ${row.id}, then re-run /sync-gbrain`,
+    };
+  }
+  return { ok: true, summary: `curated artifacts pushed; gbrain source ${row.id} has ${row.page_count} pages` };
 }
 
 export interface MemorySourceSelection {
@@ -1598,13 +1632,10 @@ function runBrainSyncPush(args: CliArgs): StageResult {
   spawnSync(discover.cmd, discover.argv, { stdio, timeout: 60 * 1000, shell: discover.shell });
   const result = spawnSync(once.cmd, once.argv, { stdio, timeout: 60 * 1000, shell: once.shell });
 
-  return {
-    name: "brain-sync",
-    ran: true,
-    ok: result.status === 0,
-    duration_ms: Date.now() - t0,
-    summary: result.status === 0 ? "curated artifacts pushed" : `gstack-brain-sync exited ${result.status}`,
-  };
+  if (result.status !== 0) {
+    return { name: "brain-sync", ran: true, ok: false, duration_ms: Date.now() - t0, summary: `gstack-brain-sync exited ${result.status}` };
+  }
+  return { name: "brain-sync", ran: true, duration_ms: Date.now() - t0, ...brainSyncIndexVerdict() };
 }
 
 /**

docs/gbrain-sync-errors.md

@@ -408,6 +408,25 @@ gstack-gbrain-install      # upgrade gbrain
 
 ---
 
+## `curated artifacts pushed to git, but gbrain source <id> has 0 indexed pages. Fix: gbrain sync --source <id>, then re-run /sync-gbrain`
+
+**Problem.** `/sync-gbrain`'s brain-sync stage is `ERR` even though the git
+push worked.
+
+**Cause.** The push only moves your curated artifacts to git. gbrain indexes
+them separately, and the artifacts source this machine maintains reports zero
+pages, so searches return nothing from it. Before this release the stage said
+"curated artifacts pushed" and passed.
+
+**Fix.**
+```bash
+gbrain sync --source <id>
+/sync-gbrain
+```
+If it stays at zero, re-register the source with `gstack-gbrain-source-wireup`.
+
+---
+
 ## Nothing is syncing but I expect it to
 
 **Not an error, but a common gotcha.** Check in order:

test/gstack-gbrain-sync.test.ts

@@ -544,6 +544,36 @@ esac
     rmSync(home, { recursive: true, force: true });
   });
 
+  // A5 (#2670): a successful git push is not gbrain indexing.
+  for (const [pageCount, ok, expected] of [
+    [0, false, "gbrain source fixture-artifacts has 0 indexed pages. Fix: gbrain sync --source fixture-artifacts"],
+    [7, true, "curated artifacts pushed; gbrain source fixture-artifacts has 7 pages"],
+  ] as const) {
+    it(`brain-sync stage reports the artifacts source's ${pageCount} indexed pages (ok=${ok})`, () => {
+      const home = makeTestHome();
+      const gstackHome = join(home, ".gstack");
+      const fakeBin = join(home, "fake-bin");
+      mkdirSync(gstackHome, { recursive: true });
+      mkdirSync(fakeBin, { recursive: true });
+      writeFileSync(join(fakeBin, "gbrain"), `#!/bin/sh
+case "$*" in
+  "sources list --json") printf '%s\\n' '{"sources":[{"id":"fixture-artifacts","local_path":"${gstackHome}","page_count":${pageCount}}]}' ;;
+  *) exit 1 ;;
+esac
+`);
+      chmodSync(join(fakeBin, "gbrain"), 0o755);
+      const r = runScript(["--incremental", "--no-code", "--no-memory", "--quiet"], {
+        HOME: home, GSTACK_HOME: gstackHome, PATH: `${fakeBin}:${process.env.PATH || ""}`,
+      });
+      const state = JSON.parse(readFileSync(join(gstackHome, ".gbrain-sync-state.json"), "utf-8"));
+      const stage = state.last_stages.find((entry: { name: string }) => entry.name === "brain-sync");
+      expect(stage.summary).toContain(expected);
+      expect(stage.ok).toBe(ok);
+      expect(r.exitCode).toBe(ok ? 0 : 1);
+      rmSync(home, { recursive: true, force: true });
+    });
+  }
+
   it("brain-sync stage resolves the sibling binary, not a HOME-rooted path", () => {
     // Regression for Codex M9: pre-fix the orchestrator looked up
     // ~/.claude/skills/gstack/bin/gstack-brain-sync, which silently no-op'd