[Docs] Explain custom MCP tool-list recovery

[roomote-community]

​Opened on behalf of @mrubens. Follow up by mentioning @roomote, in the web UI, or in Discord.

Related issue

Daily documentation accuracy audit; follows the merged tool-catalog recovery change in #3441. No separate issue.

Why this PR exists

• A maintainer explicitly invited this PR in the linked issue or discussion
• I am a maintainer / this is internal Roomote work

The audit of the 10 PRs merged between 2026-10-09T03:00:45.894Z and 2026-10-10T03:00:45.894Z found that custom MCP tool-list recovery lacked troubleshooting guidance. Existing open documentation PRs do not cover this gap. All 10 merges target develop and postdate the latest release, v1.17.0; this documentation follows develop's implementation, rather than claiming the retry control exists in v1.17.0.

What changed

Explain how to retry a failed remote custom MCP tool-list load from the same Manage tools dialog, including the visible error, disabled retry button during a request, and restored list after success.

The guidance matches CustomToolManagementDialog in apps/web/src/components/settings/CustomMcpServers.tsx and its existing recovery tests. Readers can recover a failed catalog load without recreating their server connection. No application behavior changes.

How it was tested

• mise exec -- pnpm --filter @roomote/docs check: Mintlify build validation and broken-link checks passed.
• mise exec -- pnpm --filter @roomote/docs check-cookbook-index: all seven recipes are current.
• git diff --check: passed; the final diff contains only the intended seven-line docs addition.
• Pre-push checks passed: oxlint, residual web/worker ESLint, 27 package typechecks, and Knip.
• Rendered verification was attempted with agent-browser on the configured local docs preview. It returns HTTP 500 / Internal Server Error; logs identify missing generated Mintlify Next.js build files. No screenshot or video evidence is claimed.
• The pre-commit semantic prose check returned incomplete because a supported Jev provider is unavailable. Commit succeeded; prose was manually reviewed against the repository guidance. The full semantic check remains a merge-time validation gap.

Checklist

• The PR title follows the repo convention: [Fix], [Feat], [Improve], [Refactor], [Docs], or [Chore] followed by a user-facing description
• This PR is small and scoped to one change
• pnpm lint and pnpm check-types pass locally
• I added tests or included a clear manual validation note above
• I removed secrets, tokens, private keys, and customer data from code, logs, and screenshots
• If this change should appear in the changelog, I ran pnpm changeset

The normal fast pre-push static gates passed as listed above; the formatting-inclusive lint/typecheck commands were not separately run. A changeset is not needed for this public-docs-only correction.

[roomote-community]

No issues found. The troubleshooting guidance matches the dialog's retry behavior and existing recovery tests. Docs validation, lint, type checking, and tests passed in current-head CI; other checks are still running. See task

_{Reviewed f2f939d}