zot-annotate adds /annotate, a browser-based review surface for the latest agent message. It is based on the zot-extension-template-golang layout and uses only the Go standard library.

1. Start in the TUI. After an assistant response, run /annotate.
2. Move to the browser intentionally. zot-annotate starts a loopback HTTP server on an automatically selected free port and opens the URL with the platform browser. The TUI immediately shows that the annotation session is ready; it never blocks the agent turn.
3. Review the response. The left pane presents the latest response in a readable, scrollable document. The right rail contains the review state.
4. Annotate in place. Select text with the mouse. A focused comment dialog records the exact selected text and a requested change. Multiple annotations can be added, edited by deleting/re-adding, and cleared before submission.
5. Attach context. Drag files, screenshots, or images into the attachment drop zone. Files are stored in the extension data directory and their local paths are included in the follow-up so the agent can inspect them with its normal tools.
6. Submit once. The browser posts a structured feedback package. zot-annotate sends a follow-up prompt through the extension protocol, preserving the original message, annotations, and attachment paths. The agent can then produce a revised response in the normal TUI.

This first slice deliberately uses a compact feedback package rather than trying to mutate the transcript. That keeps session history intact and makes annotation requests auditable.

go build -o zot-annotate .
zot ext install .
# restart zot, wait for an agent response, then run /annotate

For development:

zot --ext .

The embedded UI is served from ui/index.html; there is no separate frontend build step.

Configuration is read from config.json in the extension's data_dir:

{"host":"127.0.0.1"}

Supported hosts are:

• 127.0.0.1 (default): local browser only.
• localhost: local browser only.
• 0.0.0.0: listen on all interfaces. Use only on a trusted network; the UI has no authentication and can expose the latest agent message and uploaded files to anyone who can reach the port.

ZOT_ANNOTATE_HOST overrides the file setting for a single run. The port is always selected by the operating system, so multiple zot sessions do not need hard-coded port assignments.

• The extension has the same filesystem permissions as zot.
• Uploaded files are limited to 25 MiB each and saved with restrictive directory permissions under data_dir/annotations.
• The server starts only after /annotate is invoked and remains available for the lifetime of the extension process. Binding is loopback by default.
• The UI currently loads Tailwind's browser CDN script for styling. The HTML and behavior are embedded; a production packaging pass should vendor a compiled Tailwind stylesheet if offline use is required.
• Headless zot modes cannot open a browser and are not a supported UX target.