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+---
+name: Deterministic Story Lifecycle Management
+test_plan: pending
+---
+
+# Story 45: Deterministic Story Lifecycle Management
+
+## User Story
+
+As a developer running autonomous agents, I want the server to manage story file movement (upcoming → current → archived) deterministically via the REST/MCP API, so that agents cannot skip steps, move stories prematurely, or leave the board in an inconsistent state.
+
+## Acceptance Criteria
+
+- [ ] `start_agent` automatically moves the story from upcoming/ to current/ if it isn't already there
+- [ ] A new `accept_story` MCP/REST endpoint moves a story from current/ to archived/ (human-only action, not available to coder agents)
+- [ ] Agents cannot move story files directly — the server is the single source of truth for story lifecycle
+- [ ] If a story is already in current/, `start_agent` leaves it there (idempotent)
+- [ ] If a story doesn't exist in upcoming/ or current/, `start_agent` returns a clear error
+
+## Out of Scope
+
+- Workflow state machine enforcement beyond file movement (e.g. blocking archived stories from being re-opened)