diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 63498b6..0514562 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -19,3 +19,12 @@ jobs:
       - run: npm run lint
       - run: npm run typecheck
       - run: npm run test:ci
+      - run: npm run build
+      - name: Built CLI prints top-level help
+        run: |
+          node dist/index.js --help > "$RUNNER_TEMP/help.txt" 2>&1 || { status=$?; echo "built CLI exited $status — see output below"; cat "$RUNNER_TEMP/help.txt"; exit 1; }
+          grep -q '^Usage: markpost <command>' "$RUNNER_TEMP/help.txt" || { echo "top-level usage line changed — update ci.yml or HELP_TEXT in src/index.ts"; cat "$RUNNER_TEMP/help.txt"; exit 1; }
+        env:
+          # conf -> env-paths reads XDG_CONFIG_HOME on Linux only; this keeps the
+          # help smoke test off any real config store. Revisit if runs-on changes.
+          XDG_CONFIG_HOME: ${{ runner.temp }}/markpost-config