Context

Upstream heavily refactored several agent runtime files that we also modified in Sprints 3.5-3.7. Our changes are small (3-80 lines each) but upstream changes are massive (200-1200 lines each).

Conflict Files

What To Do

1. Take upstream versions for all files (their changes are much larger)
2. Re-apply our small customizations:
   • model-selection.ts: Set reasoning mode as default (3 lines — PR feat(agent): enable reasoning mode as default #78)
   • pi-tools.before-tool-call.ts: Add storm detection import (2 lines — PR feat(agents): rapid-succession storm detector + callTrace to prevent nested-agent tool storms #56)
   • tool-loop-detection.test.ts: Merge both test suites
   • history.ts: Merge our additions with upstream changes
3. For deleted test file (pi-tools.before-tool-call.test.ts): check if upstream moved tests elsewhere, then re-apply our storm detection tests there
4. Our tool-loop-detection.ts (new file) is safe — no conflict

Acceptance Criteria

• Reasoning mode default works
• Storm detection integration works
• All tool-loop-detection tests pass
• Tests pass: pnpm test

References

• Sprint 3.6 PR feat(agents): rapid-succession storm detector + callTrace to prevent nested-agent tool storms #56 (storm detector), Sprint 3.7 PR feat(agent): enable reasoning mode as default #78 (reasoning mode)
• Upstream merge base: 9f2b254