# Session 0048.0 — Transcript

> App: vscode-cowriting-plugin
> Start: 2026-06-13T08-45 (PST)
> Type: planning-and-executing
> End: 2026-06-13T08-58 (PST)
> Status: **FINALIZED.**
> Posture: autonomous (yolo)

## Launch prompt

```
/goal plan-and-execute #40 (restore exact author attribution on undo/redo — follow-up to #38)

```

## Plan

**#40 (task, P3)** — restore exact author attribution on undo/redo (follow-up to
#38). Anchor: leaf `task` → §4.3 R2 (no design gate). Picked autonomously (last
R2-eligible leaf not blocked by a content-repo/careful/irreversible gate).

#38 made undo/redo re-inserted text **neutral** (no false human coloring) but
lossy: undoing a deletion of Claude text shows it neutral, not blue. #40 restores
the **exact prior** attribution.

**Mechanism (engineering choice): text-keyed attribution snapshots.** Per-doc
`Map<documentText, spans>`; snapshot after every FORWARD edit (and at load). On
undo/redo, after the #38 geometry reconcile, if a snapshot's text equals the
current buffer, restore those spans exactly (offsets valid — text identical).
Robust to VS Code undo coalescing (only the event whose resulting text matches a
snapshot restores; far-back/evicted states fall back to #38 neutral). Bounded
history.

Tasks: snapshot+restore in `attributionController` (loadAll + onDidChange);
tests (agent-text undo restores blue; edit→undo→redo round-trip; #38 regression
green). No deploy pipeline (extension).

## Results

**#40 implemented but NOT shipped — verification-blocked.** On branch
`s40-undo-provenance` (pushed, unmerged); issue #40 **kept open**.

- `attributionController.ts` — text-keyed attribution snapshots
  (`attrHistory: Map<documentText, spans>`, `ATTR_HISTORY_MAX` bounded): snapshot
  after every forward edit + at `loadAll`; on undo/redo restore the snapshot whose
  text equals the current buffer (else #38 neutral fallback). Robust to undo
  coalescing.
- `test/e2e/suite/s40Provenance.test.ts` — agent-text-undo-restores-blue +
  edit→undo→redo round-trip.
- **222 unit + typecheck green.**

**BLOCKER (environmental, not the code):** the #40 host E2E — and the *untouched*
#38 `undoMarks` E2E — drive `executeCommand("undo")`, which does **not restore
text** in this local test instance. Proven by stashing all my changes and running
clean `main`: the #38 test fails identically (`undo restored 'bravo'`). This is the
**known undoMarks flake (session 0037), now deterministic** in this environment.
The usual remedy — clearing `.vscode-test/user-data` — is **permission-blocked**
this session (`rm -rf` denied). Focusing the doc before `undo` (`showTextDocument`)
did not help. So #40's end-to-end behavior cannot be verified here; shipping
unverified changes to the load-bearing F3 attribution controller would violate
verify-before-completion. Left on a branch for the operator to verify + merge in a
working E2E environment.

**Also surfaced:** `main`'s E2E is currently **red in this environment** for the
same environmental reason (the undoMarks `undo` flake) — a test-infra issue
independent of product code.

## Session arc

1. Stop hook required determining/executing the next milestone; chose #40 (last
   R2-eligible leaf). Claimed 0048, clean `main`.
2. Read #40 + #38 + the attribution change handler; chose text-keyed snapshots.
3. TDD: wrote #40 E2E + implemented snapshot/restore; 222 unit green.
4. E2E: 3 undo-driven tests failed at the `undo restored X` step. Isolated by
   stashing → clean `main`'s #38 test fails identically → environmental undo flake,
   not my code. Could not clear `.vscode-test` (permission-blocked).
5. Committed #40 to a branch (pushed, unmerged, marked UNVERIFIED); kept #40 open;
   stopped per verify-before-completion.

## Deferred decisions

_Autonomous-mode low-confidence calls the driver made and would have
liked operator input on. Empty if none._

- **Did not merge #40** (driver call). Alternative: merge on unit-green + reasoning
  alone. Why not: it changes the core F3 attribution controller and its behavior is
  only meaningfully provable through an undo E2E, which is environmentally broken
  here — verify-before-completion says don't claim/ship it. Preserved on a branch
  for operator verification instead. (Reversible: just merge once verified.)