Missing token.json makes tool calls hang ~120s on a browser flow instead of failing fast

[ElliotDrel]

Description

When token.json is absent, a tool call does not return a fast, actionable auth error. It blocks while waiting for an interactive browser authorization flow to be completed, and only errors out after roughly two minutes with "Google authentication required. A browser window should have opened automatically."

Impact: in a stdio MCP session inside a CLI agent, no browser window opens for the caller and nobody is watching for one, so the wait can never succeed. Two independent calls (listCalendars, getEvents) each burned ~120s and were pushed to background tasks before failing, which is a 4-minute stall on what is a one-line precondition failure.

Environment: server 3.4.6, node v22.22.3, win32 10.0.26200, transport stdio, credentialSource environment.

troubleshoot reports the state correctly and instantly:
auth.tokenFile: "missing", auth.hasRefreshToken: false, auth.status: "missing"

Expected: when auth.status is "missing" (no token file, no refresh token), every tool should short-circuit before attempting the interactive flow and return immediately with the remediation command. Launching a browser and waiting on it is only reasonable when the caller can actually see and complete it.

Suggested fixes, any of which would be enough:

1. Check auth.status at the top of the tool handler and fail fast with "No credentials. Run: npx google-tools-mcp auth" when it is "missing".
2. Do not attempt the interactive browser flow at all on the stdio transport. Suppress the browser launch and return the remediation text.
3. If the wait is kept, cut the timeout to a few seconds and make the message state plainly that the flow must be run in a separate terminal, rather than implying a browser window has already opened.

Also: the error message asserts "A browser window should have opened automatically." On a headless/stdio invocation it did not, and the wording sends the reader looking for a tab that does not exist.

Diagnostic Info

• Server version: 3.4.6
• Node version: v22.22.3
• OS: win32 10.0.26200 (x64)
• Auth status: missing
• Scopes: documents, drive, spreadsheets, script.external_request, gmail.modify, gmail.compose, gmail.send, gmail.settings.basic, gmail.settings.sharing, calendar, forms.body, forms.body.readonly, forms.responses.readonly, presentations, tasks, service.management