Two tools with basic schemas and minimal descriptions. list_unread and search_emails both have input schemas with type definitions, but descriptions are generic (10-20 chars) and lack context for LLM selection. No output schemas documented. Parameters lack depth, max_results has no range constraints, query parameter has no format guidance. No error handling guidance. Tool names follow verb_noun convention (positive), but descriptions fail to explain WHEN to use each tool or what distinguishes them. Missing idempotency hints, permission scopes, and recovery guidance.

• Expand tool descriptions to 100-200 chars. Example: 'list_unread: Retrieve unread Gmail messages with snippets. Returns up to 10 messages by default. Use this to check recent unread emails; use search_emails for filtered queries. Requires Gmail read scope.'
• Document output schema for both tools. Specify returned fields: message_id, sender, subject, snippet, timestamp, labels. Include example response structure so LLMs know what to extract.
• Add range constraints to max_results: 'Maximum number of messages to return (1-100, default: 10)'. Prevents absurd values.
• Add format guidance to query parameter: 'Gmail search query using operators: from:, to:, subject:, has:attachment, is:unread, etc. Example: from:[email protected] is:unread'
• Add error handling: Catch HttpError, OAuth failures, and rate limits. Return structured errors with recovery hints: 'Rate limited. Retry after 60 seconds.' or 'OAuth token expired. Re-authenticate via get_credentials().' Include permission scope declarations (read:email).