[MCP] Improve startup errors for timeouts and github

[gpeal]

1. I have seen too many reports of people hitting startup timeout errors and thinking Codex is broken. Hopefully this will help people self-serve. We may also want to consider raising the timeout to ~15s.
2. Make it more clear what PAT is (personal access token) in the GitHub error

[chatgpt-codex-connector]

💡 Codex Review

https://github.com/openai/codex/blob/cd05828a80134866ccffae36d88a7170c6ad1179/codex-rs/core/src/codex.rs#L3142-L3153
Align startup timeout test with new error message

The newly added timeout hint test still asserts the old message text ("MCP client for {server_name}failed to start: timed out. Addstartup_timeout_sec���"), but mcp_init_error_display now formats the timeout error as "timed out after {startup_timeout_secs} seconds. Add or adjust startup_timeout_secin themcp_servers.{server_name} section…" (see the branch just above in this file). Running the test suite will fail because the strings no longer match. The expected string in the test should be updated to mirror the new message format (including the duration and configuration path) or the production code should be reverted to the previous wording.

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[chatgpt-codex-connector]

💡 Codex Review

https://github.com/openai/codex/blob/cd05828a80134866ccffae36d88a7170c6ad1179/codex-rs/core/src/codex.rs#L3143-L3153
Update timeout hint test to match new error text

The new mcp_init_error_display branch formats timeout errors as "MCP client for {server}timed out after {startup_timeout_secs} seconds. Add or adjuststartup_timeout_secin themcp_servers.{server} section…", but the added test still expects the old generic message "failed to start: timed out. Add startup_timeout_sec…". As written, cargo test -p codex-core will fail because the strings never match. Adjust the expected string (or compute it from DEFAULT_STARTUP_TIMEOUT) so the test reflects the new behaviour.

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[pakrym-oai]

nit: consider providing an exact snippet

[gpeal]

Yup, just did

[pakrym-oai]

I mean printing something like

[mcp_servers.slow]
startup_timeout_sec = 60

that users can copy-paste

[gpeal]

Ah good idea. I was fixated on making it one line but this is better.