packages/chrome-extension/README.md
A Chrome extension that brings Qwen Code into the browser as a thin client of a
local qwen serve daemon — no Native
Messaging host to install.
It does two things:
/acp
WebSocket and bridges cdp_* frames into chrome.debugger, so the agent can
drive the real browser when an external CDP MCP adapter is configured.npm run build # -> dist/extension (static assets + bundled service worker)
Then load it: chrome://extensions → enable Developer mode → Load unpacked
→ pick dist/extension.
The extension is a client; the daemon does the work and must be started separately (an extension cannot spawn a local process). Open the side panel and it will tell you exactly what to run — it generates the command with this extension's own id:
qwen serve --allow-origin chrome-extension://<this-extension-id>
--allow-origin chrome-extension://<id> is required: it lets the daemon's Web
Shell be framed by the extension (the frame-ancestors CSP) and accepts the
extension's requests. The side panel reads the id at runtime via
chrome.runtime.id, so you never have to look it up.
Once the daemon is reachable and permits framing, the side panel swaps the welcome screen for the chat UI automatically.
The command above only makes the side panel and Web Shell available. Browser automation tools such as console/network inspection, screenshots, and page clicking require an explicit external MCP adapter command:
QWEN_CDP_MCP_COMMAND=/path/to/cdp-mcp-adapter \
qwen serve --allow-origin chrome-extension://<this-extension-id>
No browser automation adapter is bundled with the main @qwen-code/qwen-code
package. When QWEN_CDP_MCP_COMMAND is unset, the extension can still open the
Web Shell, but the daemon will not register browser automation MCP tools.
Clients can distinguish the states through /capabilities:
allow_origin means the extension may frame and call the daemon.cdp_tunnel_over_ws means the daemon exposes the reverse CDP tunnel.browser_automation_mcp means the external adapter command is configured and
browser automation MCP tools can be registered when the CDP bridge connects.The side panel probes GET /health and GET /capabilities and shows one of:
| State | Meaning | Shown |
|---|---|---|
down | no daemon reachable | "Start qwen serve" + command |
needs-allow-origin | daemon up but --allow-origin not set | "Allow this extension" + command |
ready | daemon up and framing permitted | the Web Shell (chat) |
npm run package # -> chrome-extension.zip (manifest at the zip root)
Upload the zip to the Chrome Web Store Developer Dashboard. Note that the
debugger and <all_urls> permissions will draw manual review — justify them
in the store listing.