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+---
+name: "Configurable coder pool size and default model in project.toml"
+---
+
+# Story 307: Configurable coder pool size and default model in project.toml
+
+## User Story
+
+As a project owner, I want to configure the number of concurrent coder agents and their default model in project.toml, so that I can control resource usage and cost while still being able to override per-story when needed.
+
+## Acceptance Criteria
+
+- [ ] New project.toml setting: default_coder_model (e.g. 'sonnet') determines which model is used for coder agents by default
+- [ ] New project.toml setting: max_coders (e.g. 3) limits concurrent coder agent slots
+- [ ] Add one more sonnet coder to the agent config (coder-3) for a total of 3 sonnet coders
+- [ ] When all coder slots are full, new stories wait in current until a slot frees up
+- [ ] Per-story front matter agent field still overrides the default (e.g. agent: coder-opus assigns opus)
+- [ ] Opus coders are only used when explicitly requested via front matter
+- [ ] QA and mergemaster limits are unchanged (not configurable via this story)
+- [ ] auto_assign_available_work respects the max_coders limit
+
+## Out of Scope
+
+- TBD