---
issue: 45
issue_title: "Add \"approve for this session\" option to permission prompts"
---

# Retro: #45 — Add "approve for this session" option to permission prompts

## Final Retrospective (2026-05-03T15:30:00Z)

### Session summary

Implemented session-scoped approvals for the `external_directory` permission surface across plan, TDD, ship, and release (v3.4.0).
Four feat commits added `SessionApprovalCache`, extended the permission dialog with a fourth option, wired the cache into both file-tool and bash external-directory gates, and documented the feature.
The TDD cycle caught a `deriveApprovalPrefix` edge case (trailing-separator paths) on the first red pass.

### Observations

#### What went well

- TDD red→green cycle was clean across all three feature steps.
  The `deriveApprovalPrefix` trailing-separator bug (`dirname("/other/project/src/")` strips the slash and returns the parent) was caught immediately by a failing test — fixed in seconds, no rework.
- Plan-to-implementation fidelity was high.
  The plan's `SessionApprovalCache` design, dialog extension, and `index.ts` wiring mapped 1:1 to the implementation with no structural surprises.
- The `applyPermissionGate` abstraction (from #41) made the wiring step straightforward — wrapping `promptForApproval` to capture the decision state was a clean seam.
- Ship and release were fully automated: CI green, release-please PR merged, v3.4.0 tagged.

#### What caused friction (agent side)

- `missing-context` — After committing the docs update, I did not proactively confirm that all plan-flagged documents were aligned.
  The user had to ask "All our documents are up to date?"
  to trigger verification.
  Impact: one extra user round-trip, no rework needed (docs were actually complete).
- `other` (tool fragility) — A multi-edit `Edit` call on `README.md` failed on the second edit due to an `oldText` mismatch with Unicode `→` characters in the architecture tree.
  The first edit (session-scoped approvals section) was silently lost.
  Caught during post-commit verification and fixed by amending the commit.
  Impact: minor rework (re-applied the edit and amended), ~1 minute.

#### What caused friction (user side)

- The "All our documents are up to date?"
  prompt was mechanical oversight — the agent should have provided a verification summary unprompted after the docs commit.
  No user-side change needed; this is an agent salience issue.
