diff --git a/.github/probe-api.mjs b/.github/probe-api.mjs
new file mode 100644
index 0000000..8671192
--- /dev/null
+++ b/.github/probe-api.mjs
@@ -0,0 +1,19 @@
+// Probe: connect @pezkuwi/api to the dev node and report why it does not become ready.
+import { ApiPromise, WsProvider } from '@pezkuwi/api';
+
+const provider = new WsProvider('ws://127.0.0.1:30333');
+const timer = setTimeout(() => { console.log('PROBE: not ready after 60s'); process.exit(2); }, 60_000);
+
+for (const ext of [undefined, { AuthorizeCall: { extrinsic: {}, payload: {} } }]) {
+  console.log(`PROBE: create with signedExtensions=${ext ? 'AuthorizeCall' : 'none'}`);
+  try {
+    const api = await ApiPromise.create({ provider, signedExtensions: ext, throwOnConnect: true, throwOnUnknown: true });
+    console.log('PROBE: ready', api.runtimeVersion.specName.toString(), api.runtimeVersion.specVersion.toString());
+    console.log('PROBE: extensions', api.registry.signedExtensions.join(','));
+    console.log('PROBE: has bounties', !!api.tx.bounties, 'metadata v', api.runtimeMetadata.version);
+  } catch (e) {
+    console.log('PROBE: error', e?.stack || e);
+  }
+}
+clearTimeout(timer);
+process.exit(0);
diff --git a/.github/workflows/slow-probe.yml b/.github/workflows/slow-probe.yml
index a3b59a7..f283dd7 100644
--- a/.github/workflows/slow-probe.yml
+++ b/.github/workflows/slow-probe.yml
@@ -20,6 +20,8 @@ jobs:
           done
           echo; docker logs node 2>&1 | tail -5
       - run: corepack enable && yarn install --immutable
+      - name: api probe
+        run: node .github/probe-api.mjs 2>&1 | tail -40
       - name: Bounties spec (4 min cap)
         run: timeout -s INT 240 yarn test:one :Bounties.slow. ; echo "rc=$?"
       - name: CreateAccount spec (4 min cap)