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+---
+name: "Auto-assign assigns mergemaster to coding-stage stories"
+---
+
+# Bug 312: Auto-assign assigns mergemaster to coding-stage stories
+
+## Description
+
+Auto-assign picks agents whose configured stage doesn't match the pipeline stage of the story. Observed multiple mismatch types:
+
+- **Mergemaster assigned to coding-stage stories**: Story 310 was in `2_current/` but got mergemaster instead of a coder (2026-03-19)
+- **Coders assigned to QA-stage stories**: Coders (stage=coder) have been observed running on stories in `3_qa/`
+- **QA agents assigned to merge-stage stories**: QA agents (stage=qa) have been observed running on stories in `4_merge/`
+
+The `auto_assign_available_work` function doesn't enforce that the agent's configured stage matches the pipeline stage of the story it's being assigned to. Story 279 (auto-assign respects agent stage from front matter) was supposed to fix stage matching, but the check may only apply to front-matter preferences, not the fallback assignment path.
+
+## How to Reproduce
+
+1. Move a story to any pipeline stage with no agent front matter preference
+2. Wait for auto_assign_available_work to run
+3. Observe that agents from the wrong stage get assigned (e.g. mergemaster to coding, coder to QA)
+
+## Actual Result
+
+Agents are assigned to stories in pipeline stages that don't match their configured stage. Mergemaster codes, coders do QA, QA agents attempt merges.
+
+## Expected Result
+
+Only coder-stage agents should be assigned to stories in 2_current/. Mergemaster should only be assigned to stories in 4_merge/.
+
+## Acceptance Criteria
+
+- [ ] auto_assign_available_work checks that the agent's configured stage matches the pipeline stage of the story before assigning
+- [ ] Coder agents only assigned to stories in 2_current/
+- [ ] QA agents only assigned to stories in 3_qa/
+- [ ] Mergemaster only assigned to stories in 4_merge/
+- [ ] Fallback assignment path respects stage matching (not just front-matter preference path)