Three tools with clear verb-noun naming (list_, search_, get_). All have descriptions (avg 95 chars, within baseline 34-392). Input schemas present with Zod validation. However, output schemas are undocumented, responses are JSON-stringified without field documentation. Parameter descriptions are adequate but lack format constraints (e.g., no regex for search keywords, no enum for bookstore IDs). Error handling returns user-facing messages but lacks recovery guidance or error classification. No tool annotations (readOnlyHint, idempotentHint). Missing pagination support on search_ebooks despite potentially large result sets.

• Document output schemas for all tools. Define the structure of bookstore objects (fields: id, name, status, url), search results (fields: bookstore_id, title, author, price, url, availability), and search metadata (fields: search_id, timestamp, total_results). Include these in tool descriptions or as a separate schema reference.
• Add tool annotations: set readOnlyHint=true on all three tools (they only read data, never modify). This signals to LLMs that calls are safe to retry and do not have side effects.
• Implement pagination on search_ebooks. Add 'offset' and 'limit' parameters (default limit=20, max=100). Return 'total_count' and 'has_more' in response. Document in description: 'Results are paginated; use offset/limit for large result sets.'
• Enhance error messages with recovery guidance. Instead of 'Upstream API request failed', return 'Upstream API request failed (timeout). Retry with a smaller maxResultsPerBookstore or check API status at [url].' Classify errors: retryable (timeout, 5xx), user-fixable (invalid bookstore ID), fatal (auth failure).
• Add parameter constraints. Define 'keywords' as min 1 char, max 200 chars. Fetch valid bookstore IDs from list_bookstores and document as enum or validation rule. Set 'maxResultsPerBookstore' bounds: min=1, max=50 (default=3).