Complete tasks 3-7: harden verdict parsing, outputs retention, base branch, linux schedule parity, claim loop task

config.md

@@ -60,6 +60,18 @@ Requirements for the environment the framework runs in.
 - **/proc/meminfo**: Required for RAM detection (Linux)
 - **sysctl**: Fallback for RAM detection (macOS)
 
+## Loop Role Models
+
+Loop ticks run three session roles. Roles are *sessions*, not models — a single model can fill multiple roles. Configure each loop's role-to-prompt binding in its `loop.json`; this section documents the framework's expectations only.
+
+- **Implement:** — produces the artifact for this tick. Bound to `prompts/loop-implement.md` by default.
+- **Verify:** — grades the artifact and emits the JSON verdict `{pass, score, reasons, next_hint}`. Bound to `prompts/loop-verifier.md`. The framework never inspects this role's model (D8); only its session.
+- **Orchestrate:** — applies the verdict, calls exactly one `status.py` operation per tick, enforces brakes. Bound to `prompts/loop-orchestrate.md`.
+
+Conflict-of-interest rule (D12): `Verify:` and `Implement:` must never be the same *session*. When two distinct sessions are infeasible (single-session harness), the runner falls back to session-only divergence — still safe.
+
+Role context tiers are set per-loop in `loop.json`, not globally. The 16k floor (D13) applies regardless of tier.
+
 ## Framework Version
 
 - **Version**: 2.0