Failed MCP launches show as failed without an error reason

[RDalziel]

Short summary

Failed MCP launches show as failed without an error reason

Affected version or release

v0.2.5

Installation context

GitHub App with MCP servers configured via npx

What happened?

When an MCP server launch fails in GitHub App, the UI marks the MCP as failed but does not surface any reason for the failure. We are currently seeing this with MCP servers configured using npx.

The failed state is visible, but there is no accompanying error detail to explain whether the launch failed because of command resolution, package install problems, permissions, arguments, environment, or another startup error.

Steps to reproduce

1. Configure an MCP server in GitHub App that launches via npx.
2. Start or reconnect the MCP so GitHub App attempts to launch it.
3. Cause the launch to fail, for example with an invalid package name, invalid arguments, or another startup error.
4. Observe that the MCP is shown as failed.
5. Observe that no failure reason or actionable error details are shown.

Expected behavior

When an MCP launch fails, GitHub App should show the reason for the failure so the problem can be diagnosed. Even a concise launch error, stderr snippet, or exit code would make the failure actionable.

Additional context

This is currently affecting our MCP servers that are configured with npx.