Server has 7 tools with clear action verbs and mostly complete schemas. Descriptions are present and reasonably detailed (avg ~150 chars), exceeding the 10-char minimum. All tools have typed input parameters with descriptions. However, output schemas are not formally documented, responses are inferred from code inspection. Parameter descriptions lack constraint details (ranges, formats, enums). Error handling is minimal; no recovery guidance or actionable error messages visible. Tool composition is sound (single responsibility), but some tools could benefit from richer context (e.g., run_report lacks examples of valid metric/dimension names). Security is handled server-side via GOOGLE_APPLICATION_CREDENTIALS, which is correct.

• Add formal output schema documentation to each tool. Use JSON Schema to define return object structure, field types, and required fields. Example: list_account_summaries returns {account: string, account_display_name: string, properties: [{property: string, property_id: string, display_name: string}]}.
• Enrich run_report and run_realtime_report descriptions with links to GA4 metric/dimension reference or embed a small list of common examples (activeUsers, conversions, date, country). Add parameter constraints: metrics and dimensions must be non-empty arrays; dates must be YYYY-MM-DD or relative forms.
• Implement error handling with actionable messages. Wrap API calls in try-catch; return structured errors like {error: 'property_not_found', message: 'Property 123 not found. Call list_account_summaries() to discover valid property IDs.', recovery: 'list_account_summaries'}.
• Add pagination to list_* tools. Accept optional limit (default 20, max 100) and offset parameters. Return {items: [...], total: N, offset: M, limit: L} so agents can iterate over large result sets.
• Document parameter constraints in descriptions. For create_custom_dimension, specify: display_name length 1-40 chars, scope must be one of [EVENT, USER, ITEM], parameter_name must match [a-zA-Z0-9_]+ pattern.