The graphlemon Work Node (coder) workflow completed successfully. Summary:

- Added a single documentation comment above `_LOOP_LIMIT = 3` in `src/org_loop_route.py`, referencing REQ-05/REQ-09 (docs/sdd/06-验收与测试锚点.md) to explain the `loop_round >= _LOOP_LIMIT` → `blocked_pending_human` boundary.
- `git diff` confirms a minimal, scoped change: 1 line added, 0 removed, only that file touched — matching the SDD scope exactly.
- Ran `python3 -m unittest src.test_org_loop_route -v`: all 11 existing tests pass, including `test_third_route_attempt_at_limit_blocks_and_raises`, which directly exercises the loop-limit boundary now documented. No new tests were added since this was a documentation-only change and the SDD acceptance criteria treats the existing suite as the regression proof.