chat

Interactive Chat Mode

Launch a web agent in interactive chat mode. The agent opens a browser and a chat panel. You type instructions in the chat, the agent reads the page and takes actions.

Requires only: pip install "bg-chat-minimal @ git+https://github.com/xhluca/bg-chat-minimal.git" + playwright install chromium

Arguments

Parse the following from $ARGUMENTS:

• --base-url: vLLM endpoint URL (default: https://a3-qwen-vllm.mcgill-nlp.org/v1)
• --model: Model name served at the endpoint (default: auto-detected from /v1/models)
• --start-url: Starting URL for the browser (default: about:blank)
• --ui: window (chat in a separate Chromium window — default, recommended) or overlay (chat injected into the page via a Chrome extension, single window; experimental, may break on sites with strict CSP or custom layouts)

Steps

1. Install

pip install "bg-chat-minimal @ git+https://github.com/xhluca/bg-chat-minimal.git"
playwright install chromium

2. Set up virtual display (headless servers only)

If there is no $DISPLAY set (headless server), set up Xvfb:

apt download xvfb x11-xkb-utils xkb-data libxfont2

Extract the debs into a local directory, then binary-patch Xvfb to use the local xkbcomp:

1. Extract all .deb files with dpkg-deb -x into a local directory
2. Copy xkbcomp to /tmp/xkb/
3. Copy the Xvfb binary and use sed to replace the hardcoded /usr/bin\x00 with /tmp/xkb\x00 (same byte length)
4. Start the patched Xvfb: Xvfb.patched :99 -screen 0 1920x1080x24 -ac &
5. Set DISPLAY=:99

If $DISPLAY is already set, skip this step entirely.

3. Launch

bg-chat --base-url <BASE_URL> [--model <MODEL>] [--start-url <START_URL>] [--ui <UI>]

Replace <BASE_URL>, <MODEL>, <START_URL>, and <UI> with the resolved argument values. If --model was not provided, omit it (bg-chat auto-detects from the endpoint). If --ui was not provided, omit it (defaults to window).

The viewport is 1470x720 by default.

4. Report to the user

Tell the user:

• The agent is running and waiting for chat input
• How to interact (if display is forwarded) or how to set up VNC/noVNC to view the browser
• The process PID so they can stop it later with kill <PID>
• Type "exit" in the chat to stop the session

Example tasks for A3-Qwen

Suggest one of these to the user when they're not sure what to ask the agent:

• flights.google.com — show me the 3 cheapest flights from sf to rio for april 22-28 with 2 stops or less
• booking.com — what are the 3 cheapest stays with rating of 8+ in Rio for april 22-28? focus on hotels with breakfast included
• resy.com — find 3 highly-rated japanese restaurants in LA with availability for 2 people on April 23