# Session 0004.0 — Transcript

> App: vscode-cowriting-plugin
> Start: 2026-06-10T06-38 (PST)
> Type: planning-and-executing
> End: 2026-06-10T07-04 (PST)
> Type: planning-and-executing
> Status: **FINALIZED.**
>
> Driver session for Feature #4 (F2 — region-anchored threads): wrote the
> just-in-time plan from the graduated coauthoring-inner-loop spec and executed
> all five slices. Shipped to `main` via Gitea PR #5.

## Launch prompt

Build **F2 (#4) — region-anchored threads** in a planning-and-executing session:
write the just-in-time plan from `vscode-cowriting-plugin-content/specs/coauthoring-inner-loop.md`
(§7.2 SLICE-1..5: CoauthorStore → Anchorer → ThreadController via the Comments API →
reload/external re-anchor → `@vscode/test-electron` E2E) and execute it. UI surface ⇒
E2E host tests are first-class plan tasks. No live `@cline/sdk` turn / no provider-auth in F2.

## Plan

Implementing the **coauthoring inner-loop** spec (graduated, session 0003), first consumer
F2 (#4): region-anchored discussion threads on the POC skeleton (#2).

Slices (spec §7.2), each a plan task:

- **SLICE-1** Artifact schema (`schemaVersion`, shared `anchors`/`provenance`, `threads`) +
  `CoauthorStore` (load/save `.threads/` sidecars, stable key ordering, round-trip tests). [vscode-free, vitest]
- **SLICE-2** `Anchorer` — `buildFingerprint`, resolution ladder (exact-unique →
  context-disambiguated via lineHint → orphaned), live offset `shift`. [vscode-free, vitest]
- **SLICE-3** `ThreadController` wiring to `vscode.comments` (create-on-selection, reply,
  resolve, render). [editor-facing]
- **SLICE-4** Reload + external-change re-anchoring (`FileSystemWatcher`) + orphaned-thread surface.
- **SLICE-5** E2E (`@vscode/test-electron`) across create→persist→reload→re-anchor; fall back
  to driving the `ThreadController` API + asserting Comments-controller state where the harness
  cannot drive native Comments UI.

Invariants: never silently move a thread (orphan instead, INV-1); git-native serverless JSON
(INV-2); fingerprint is source of truth (INV-3); forward-compatible envelope for F3–F5 (INV-4);
no live `@cline/sdk` turn / no credentials (INV-5). Done = F2 acceptance met, unit + host E2E green.

Plan doc: `docs/superpowers/plans/2026-06-10-f2-region-anchored-threads.md`
(archived to `vscode-cowriting-plugin-content/plans/`).

## Session arc

**Pre-state:** clean `origin/main` at the POC skeleton (#2, sessions 0002/0003).
Spec `coauthoring-inner-loop.md` graduated in brainstorming session 0003.

1. **Claim + orient** — claimed session 0004; read the spec (§6 design, §7.2
   slices) and the POC skeleton (vscode-free `cline.ts`, esbuild CJS bundle with
   `vscode`/`@cline/sdk` external). Memory confirmed F2/#4 as next.
2. **Plan** — wrote the just-in-time plan with `superpowers:writing-plans`: six
   tasks (SLICE-1..5 + README/verify), every step with complete code and TDD
   grain, E2E host tests as first-class tasks. Branched `feat/f2-region-anchored-threads`.
3. **Execute** with `superpowers:executing-plans`, inline (tasks are
   type-dependent, not independent):
   - SLICE-1 `model.ts` (schema + stable serialize) + `store.ts` — 8 unit tests.
   - SLICE-2 `anchorer.ts` (fingerprint, ladder, shift) — 9 unit tests.
   - SLICE-3 `threadModel.ts` (4 tests) + `threadController.ts` + `package.json`
     contributions + `extension.ts` API. Typecheck caught `CommentThread.range`
     being optional → guarded.
   - SLICE-4 reload/watcher/orphan mechanics (built in S3) + `reanchor.test.ts`.
   - SLICE-5 `@vscode/test-electron` host E2E. Two iterations: mocha UI mismatch
     (`bdd`→`tdd`), then the external-change test needed `files.revert` because
     `openTextDocument` serves the cached buffer. 4/4 host tests green vs VS Code
     1.124.0.
4. **Ship** — full sweep green (typecheck, 24 unit, build, 4 E2E). Pushed branch,
   opened Gitea PR #5 via API, merged (autonomous), synced main, pruned branch.

**Cut state:** `main` clean & pushed; F2 shipped; 24 unit + 4 host E2E green;
plan archived; memory updated.

## Deferred decisions

- **CoauthorStore is vscode-free (Node `fs`); the `FileSystemWatcher` lives in
  ThreadController, not in the store.** Spec §6.2/§6.4 lists the watcher under
  CoauthorStore ("emits `onExternalChange`") yet also calls the store one of the
  three *vscode-free, unit-testable* units. Those pull apart — a `FileSystemWatcher`
  is a vscode API. Resolved in favor of testability (the spec's stated reason for
  vscode-free): the store does pure load/save (unit-tested), and the watcher →
  reload → re-render wiring sits in the controller and is covered by host E2E.
  Alternative was a vscode-free event emitter on the store with the watcher
  injected — more indirection for no test benefit. Low-stakes; flagging for spec
  alignment when F3/F4 touch the store.