Cognitive Atoms — VS Code extension

Capture coding cognition — the decisions and the why behind your code — into your local Cognitive Atoms Continuity Graph, from inside the editor.

This is the #2 capture surface in the plugin adoption strategy (docs/gtm/PLUGIN_ADOPTION_STRATEGY.md, P1): the editor is where builders do their hardest reasoning, and the "why" behind code is the single most painful thing that evaporates when you reopen a repo cold. It reuses the exact same normalized capture contract as the browser extension, so VS Code captures flow through the identical local ingestion pipeline — provenance is the only thing that differs.

Status: built, not published. Marketplace / Open-VSX publishing is a Founder-GO decision (ACTIVE_OPERATING_MODEL.md §3 / strategy §3). The publisher field is a placeholder. Nothing here lists or ships itself.

What it captures

Six commands (Command Palette + editor right-click on a selection):

Each command captures the current selection (or, if there is no selection, a note you type). The cue word is prefixed to the body so the existing server-side cognition_engine detection rules classify it — no special backend channel.

Payload parity with the browser extension

The payload is produced by src/capture.ts, a faithful TypeScript port of apps/browser_extension/capture_core.js. Same shape, same cues, same rules:

{
  "source_type": "VSCODE_BROWSER_EXTENSION",   // configurable rail (provenance only)
  "provider": "VSCODE",
  "provider_hint": "VSCODE",
  "url": "",
  "title": "myrepo — src/net.ts",              // provenance, not code
  "captured_at": "2026-06-06T00:00:00.000Z",
  "capture_kind": "mark:decision",             // "mark:<intent>" | "selection"
  "capture_intent": "decision",
  "messages": [
    { "index": 0, "role": "user",
      "text": "Decision: retry with backoff\n\nNote: thundering herd otherwise",
      "source_selector": "src/net.ts:5-9" }    // file + line range, never the code body
  ]
}

Why the *_BROWSER_EXTENSION rail? The runtime accepts a pre-structured messages[] payload only on the *_BROWSER_EXTENSION rails (see backend app.py). The CLAUDE_CODE_SESSION rail — the natural coding rail — requires a .jsonl transcript file on disk, not a live note, so it can't carry an in-editor capture. We therefore ride a *_BROWSER_EXTENSION rail. As of VSCODE-EXT-001 there is a first-class VSCODE_BROWSER_EXTENSION source type (provider VSCODE) so in-editor captures self-identify honestly instead of borrowing CLAUDE_BROWSER_EXTENSION; it is the default, configurable via cognitiveAtoms.sourceType. Provider is provenance only; every rail flows through the same pipeline (deterministic AtomIDs, secret redaction).

Transport (local-only, honest offline)

src/transport.ts is the sole network actor — the editor analogue of the browser extension's service_worker.js:

1. Probe GET <backendUrl>/health.
2. POST <backendUrl>/ingestion/preview (dry run).
3. POST <backendUrl>/ingestion/commit with { project_id, redact_secrets: true }.

A loopback-only guard refuses any non-loopback base URL before any request — nothing can leave the machine. When the runtime is offline the capture is not saved and you get a calm warning ("Your capture was NOT saved…") — never a fabricated success.

Privacy — mirror-never-infer

• Every capture is explicitly user-invoked via a command. No listeners, no auto-capture, no polling, no file scraping, no telemetry.
• Only the text you select or type is captured. The file path + line range are attached as provenance, never the surrounding code body. Set cognitiveAtoms.includeFileContext: false to omit even that.
• Network is loopback-only; no cloud relay.

Settings

A status-bar item shows connected / offline and re-checks on click.

Build & test

cd apps/vscode_extension
npm install
npm run compile     # tsc → out/
npm test            # node --test on the compiled pure functions (no VS Code host)

The unit tests cover the pure capture/normalize + transport-guard logic and run under plain Node — no VS Code Extension Host required. Driving the actual commands / status bar needs the VS Code host (@vscode/test-electron), which is left for a host-equipped environment.