[Bug]: T3 Connect public MCP URL is not discoverable in a single-machine setup #17216

Summary

A user with only one registered machine/environment reports that they cannot discover or copy its public MCP URL after enabling T3 Connect. Settings → Connections does not expose an apparent Copy MCP URL action for the local environment, and t3 connect status reports that the environment link is provisioned without displaying its hostname or public URL.

This blocks external MCP onboarding for ChatGPT/Claude even though the environment has been provisioned.

Environment and evidence scope

• macOS, T3 Code desktop nightly 0.0.46-nightly.20261008.2813.
• One registered machine/environment; T3 Connect signed in and enabled for that environment.
• The reproduction and workaround below are a user report, not an independently tested reproduction. The behavior with multiple machines has not been established by this report.

Steps to reproduce (reported)

1. Start T3 Code on macOS with only one registered machine/environment.
2. Sign into T3 Connect and enable it for the only environment.
3. Open Settings → Connections and look for a way to copy that environment's public MCP URL.
4. Follow the outside-agents documentation's instruction to open the environment menu and choose Copy MCP URL. In this single-machine setup, the user cannot find that action or an apparent alternate environment/menu through which to obtain it.
5. As a fallback, run t3 connect status. For the environment link, it shows Environment link: provisioned, but no hostname or public URL.

Expected behavior

Copy MCP URL should be visible for each provisioned local environment regardless of the number of registered or connected machines, with a discoverable way to copy the public T3 Connect MCP URL needed by hosted clients.

Alternatively, t3 connect status should display the environment's public URL (ideally including the MCP URL) when provisioned.

Actual behavior

The public MCP URL is not discoverable through the reported single-machine UI flow or CLI status output. Provisioning is visible, but the address needed for external MCP setup is missing.

Documentation mismatch

• Outside agents — Get the MCP URL directs users to a saved environment's menu in Settings → Connections to copy the MCP URL. It also explains that hosted agents need an internet-reachable T3 Connect address. In the reported setup, there is no apparent menu/action for obtaining the only local environment's public URL.
• Remote access — T3 Connect describes enabling T3 Connect on the host and choosing the environment from another device. A user onboarding an external MCP client with only one machine has no apparent route to the required public URL.
• T3 Connect troubleshooting points to t3 connect status for saved authorization/link configuration, but its reported provisioned status does not provide the address.

Reported workaround and impact

The user could only find the relay host by grepping local T3 logs, then reported validating the OAuth protected-resource endpoint for that host. This suggests the missing step is URL discovery; it does not establish that full MCP onboarding succeeds.

Users should not need to inspect private logs to obtain the URL required to add T3 Code as an external MCP server in ChatGPT or Claude. The normal onboarding flow is blocked at the URL-entry step.

No user-specific relay URL, hostname, local path, account identifier, credentials, or private log contents are included in this report.

Duplicate search

Searched upstream open and closed issues for single machine, Copy MCP URL, T3 Connect, and MCP endpoint URL, plus related MCP URL and single-environment terms. No exact duplicate was found.