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+<!-- agents-md-role: dev -->
+
+# AGENTS.md — dev role
+
+> Open-standard agent contract per [agents.md](https://agents.md).
+> Companion to `CLAUDE.md` (Claude-specific) — this file works for any
+> AI coding agent (Cursor, Aider, Codex, OpenHands, etc.).
+
+## Dev environment tips
+
+- Default branch convention: `main` = prod, `dev` = rolling integration,
+  `release/*` = release candidates, `feat/*` = ephemeral feature branches.
+  If this repo currently uses something else (`im-dev`, `bundle`,
+  `4411-1`, `release`, `20260203`), see
+  `dasheng-repos/.omc/notes/packing-machine-arch-2026-04-27.md` for the
+  migration plan.
+- For Vue 3 + Vite repos: `npm run build-only` (not `npm run build`)
+  to bypass legacy `tsc` errors that block clean builds.
+- For Flutter repos: `flutter pub get && flutter test` before any change.
+- For Swift repos: `xcodebuild -workspace ... -scheme ... test` from the
+  workspace root.
+
+## Testing instructions
+
+- TDD-first. Diff that changes behavior MUST add or update a test that
+  fails on the parent commit and passes on this branch.
+- Find existing tests by language:
+  - `tests/`, `core/tests/`, `__tests__/` (Python / JS)
+  - `test/`, `integration_test/` (Flutter / Dart)
+  - `*Tests/` (Swift)
+- Run with the lightest scope that proves the change:
+  `pytest core/tests/test_<module>.py` / `vitest run <pattern>` /
+  `flutter test test/<file>` / `xcodebuild test -only-testing:<TestClass>`.
+- Pre-existing failures unrelated to your change are NOT in scope to fix
+  unless explicitly requested. Note them in your PR body.
+
+## PR instructions
+
+- Title: `<type>(<scope>): <subject>` lowercase, no trailing period.
+- Body: `Why:` + `How:` + `Refs:` + `Co-Authored-By:` trailer.
+- Default branch is read at runtime — never hardcode `"main"` in
+  PR-create / merge calls. See `wen_shu_hub.auto_pr_botdev` for the
+  canonical pattern.
+- Idempotency: any artifact (issue, PR, comment) the agent creates MUST
+  carry an idempotency key in body so re-runs dedupe. Pattern:
+  `<!-- idem:<sha16> -->`.
+
+## Hard rules (production-incident-driven)
+
+1. **Fail-closed defaults** when uncertain about routing / permissions /
+   platforms. Default to the safer outcome (no fan-out, no auto-promote,
+   no auto-merge). See `_MODULE_PLATFORMS` in
+   `claude-worker-universe/core/wen_shu_hub.py` for the canonical pattern.
+2. **Portable links only.** Never write `/Users/...` in commits, issues,
+   comments, or test artifacts. Use Gitea web URL with per-segment UTF-8
+   percent-encoding. Helper: `_qa_spec_gitea_url`.
+3. **No inline PAT in remote URL.** If you see
+   `https://oauth2:<token>@host/...` in a remote, that's an existing
+   smell — don't propagate.
+
+## References
+
+- Master design: `claude-worker-universe/.omc/notes/master-design.md`
+- Build machine review: `dasheng-repos/.omc/notes/packing-machine-arch-2026-04-27.md`
+- Big-co patterns reused: Stripe Idempotency, Linear AI agents,
+  GitHub Copilot for Issues, Datadog rolling-3-window WARN, AWS IAM
+  fail-closed.