Thread preview

The desktop agent can serve a Bun dev server from any project and embed it inside the thread. Skill: images/opencode/seed/skills/preview, CLI: ob-preview.

Usage

ob-preview up   --session SESSION DIR        # serve a directory (auto-detect entry)
ob-preview up   --session SESSION --entry FILE
ob-preview status --session SESSION
ob-preview down --session SESSION

The agent includes one reply marker to embed it:

![title](open-bot://preview)

How it reaches the browser

1. ob-preview binds a port in the allowlist 4700–4719 and registers it under ~/.open-bot.
2. The control plane proxies that port through a capability-token frame URL: /api/preview/frame/<token>/.
3. On a wide screen the dashboard lifts the iframe into a resizable pane beside the thread; on a narrow screen it covers the viewport.