Visual Feedback Loop

Capture, inspect, and compare visual output from a running web app during iterative development.

How It Works

Agent (CLI)                     Server                            Browser
     |--- GET /api/dev-screenshot -->|--- SSE "capture" ----------->|
     |    ?param=value               |                              |-- capture canvas
     |                               |<-- POST { dataUrl } ---------|
     |                               | writes:
     |                               |   .screenshots/{UTC}.webp
     |                               |   .screenshots/{UTC}.json  (metadata)
     |                               |   .screenshots/latest.webp (convenience copy)
     |<-- { ok, path, latest } ------|

Agent can't access the browser directly. Server relays: GET triggers → SSE notifies browser → browser captures and POSTs back → GET resolves.