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+---
+name: Deterministic Story Mutations with Auto-Commit
+test_plan: pending
+---
+
+# Story 46: Deterministic Story Mutations with Auto-Commit
+
+## User Story
+
+As a developer running autonomous agents, I want all story file mutations to happen through server MCP/REST tools that auto-commit to master, so that the story board is always consistent, always committed, and agents never edit story files directly.
+
+## Acceptance Criteria
+
+- [ ] `create_story` auto-commits the new story file to master after creating it
+- [ ] `accept_story` auto-commits the move from current/ to archived/ on master
+- [ ] `start_agent` auto-commits the move from upcoming/ to current/ on master
+- [ ] New MCP tool `check_criterion(story_id, criterion_index)` checks off an acceptance criterion and auto-commits to master
+- [ ] New MCP tool `set_test_plan(story_id, status)` updates the test_plan front matter field and auto-commits to master
+- [ ] All auto-commits use deterministic commit messages (e.g. "story-kit: accept story 42")
+- [ ] Agents never need to edit story markdown files directly — all mutations go through server tools
+
+## Out of Scope
+
+- Locking/concurrency control for simultaneous story mutations (can be a follow-up)