my-pi/pi-permission-system/docs/retro/0051-generalize-session-approvals.md

issue, issue_title

issue	issue_title
51	Generalize session approvals to all permission surfaces with wildcard patterns

Retro: #51 — Generalize session approvals to all permission surfaces with wildcard patterns

Final Retrospective (2026-05-04T23:36Z)

Session summary

Implemented generalized session approvals across all permission surfaces (bash, mcp, skill, tools) in 6 commits released as v4.3.0. The work added a pattern-suggest module, extended checkPermission session evaluation to all surface branches, wired the gate with sessionApproval pass-through, made the dialog label dynamic, and threaded sessionLabel through the full prompt chain. 44 new tests (754 → 798), all green, no breaking changes.

Observations

What went well

• TDD cycle was clean across all 5 steps — every step went red→green on first implementation attempt with no rework.
• The existing evaluate() engine handled cross-surface session rules without modification; the work was purely additive at the checkPermission and handler layers.
• The suggestSessionPattern design as pure functions with no IO made step 1 trivially testable.

What caused friction (agent side)

• missing-context — The plan's "Module-Level Changes" listed tool-call.ts, permission-gate.ts, permission-dialog.ts, and permission-prompts.ts for step 5, but the actual sessionLabel threading required changes to src/handlers/types.ts, src/forwarded-permissions/polling.ts, and src/runtime.ts (the full callback chain). I had to trace the chain at implementation time: deps.promptPermission → runtime.promptPermission → confirmPermission → requestPermissionDecisionFromUi. Impact: ~5 extra read/grep calls to map the chain before writing code. No rework, but added friction.
• missing-context — First Edit attempt on tests/handlers/tool-call.test.ts failed with "Found 2 occurrences" because the file had two identical closing sequences (expect(result).toEqual({});\n });\n});\n). Impact: one failed tool call, immediate retry with wider context. Self-identified.

What caused friction (user side)

• No significant friction from the user side. The plan was well-specified and the session flow was smooth.

Changes made

1. Added planning guidance to AGENTS.md (Testing section): plans must list every file in callback/threading chains, not just entry and exit points.