Test an app on localhost

TaloTrace’s browser runs in the cloud. A tunnel from your laptop carries the page, and any API it calls, to that browser. The app keeps its localhost address in the browser, in your code and in the run. Never rewrite a URL or add a host name for TaloTrace.

Through your coding agent

Start your dev server, then ask your agent to verify. The MCP server opens the tunnel itself when start_run has a plain-HTTP loopback start page such as http://localhost:3000:

• It waits up to 15 seconds for the tunnel and otherwise answers LOCAL_TARGET_NOT_CONNECTED with the port.
• A second run on the same port reuses the tunnel.
• The tunnel closes after the idle time you set with mcp --idle, and when the agent exits.

A page and its API on two ports

When the page calls an API on another local port, list both. Port 3000 is the page and 3001 is the API:

talotrace connect 3000 3001

Through the agent, pass the extra ports in the target of start_run ("ports": [3001]), or start the server with mcp --ports 3001. At most eight ports go in one session. Without the API’s port the API calls fail.

Intercept mode

A local web run keeps your localhost address as its entry URL. Requests to it travel through your tunnel to your laptop. Register OAuth callbacks for localhost exactly as you do when you run the app locally.

From the command line

talotrace connect 3000       # serve the page until you press Ctrl-C
talotrace doctor --ports 3000
talotrace run <scenario id>  # starts a run; it does not say whether it passed

For a CI job use talotrace check, which owns its tunnel. See exit codes.

Who owns a tunnel

A tunnel is visible only to the sign-in that opened it. An API key and a browser sign-in cannot share one. If a run is refused with LOCAL_TARGET_NOT_CONNECTED, use the same credential for both. See Sign in.

You can hold up to five sessions at once. Ctrl-C ends a session within two seconds.