Single tool 'yugioh-api' has a comprehensive JSON Schema with 24 parameters, all typed and constrained with enums/ranges. Description is adequate (44 chars) but minimal. Parameter descriptions are present and specific (e.g., 'Filter by exact card name'). However, output schema is completely undocumented, the tool returns raw API response body as a string with no guidance on structure, fields, or how to parse results. No error handling guidance. Tool name lacks action verb (should be 'search_cards' or 'get_cards'). No pagination guidance despite potentially large result sets.

• Rename tool from 'yugioh-api' to 'search_cards' or 'get_cards' to start with an action verb matching pattern:tool naming conventions.
• Document output schema explicitly. Specify that response is JSON with fields like 'data' (array of card objects), 'card_id', 'card_name', 'card_type', 'atk', 'def', etc. Include example structure.
• Add pagination guidance: 'Results are limited to 100 cards per call. Use 'num' to limit results (1-100) and 'offset' to paginate. Always check response length to detect end of results.'
• Implement structured error responses. Instead of 'Error: <message>', return JSON with 'error_code' (e.g., 'INVALID_FILTER', 'API_TIMEOUT', 'NOT_FOUND'), 'message', and 'recovery_hint' (e.g., 'Try with fewer filters' or 'Retry in 30 seconds').
• Expand tool description to 80-150 chars: 'Search Yu-Gi-Oh! card database by name, type, stats, archetype, or format. Returns matching cards with full details. Use filters to narrow results; pagination via num/offset.'

Inferred effective spec: <=2025-11-25.

• Relies on Logging (deprecated) - log to stderr or use OpenTelemetry