This e-commerce MCP server presents 16 well-structured read-only tools with consistent naming patterns and documented schemas. However, the tool definitions reveal moderate gaps in parameter descriptions, missing output schema documentation, and inconsistent depth across tools. The server demonstrates competent implementation of basic patterns but falls short of production-grade quality expected at 70+. Parameter descriptions are present but often terse (e.g., 'product availability filter' lacks format/constraint detail). Output schemas are inferred from code but never explicitly documented in tool definitions. Error handling is minimal, tools return empty objects or bare errors with no recovery guidance. Tool naming follows verb_noun conventions well (list_, search_, products_by_), but some tools could be more discoverable with better descriptions. The server is suitable for internal/demo use but needs refinement for production agent deployment.

• Document the output schema for every tool. Add a 'Returns' section to each tool's docstring or register tool output schemas in the FastMCP definition. Example for products: 'Returns a list of product objects with fields: id (int), title (str), price (float), category (str), brand (str), platform (str), available (bool), sale_price (float|null), external_id (str), affiliate_store_id (int).'
• Expand parameter descriptions to include constraints and format details. Example: 'limit (int, 1 - 1000, default 50): maximum number of products per page.' or 'available (bool, default null): filter by availability; null returns all products.'
• Add pagination (limit/offset) to tools that return large result sets (products_search, products_by_brand, products_by_category, affiliate_store_products). Include total_count in responses so LLMs know if results are truncated.
• Replace silent failures with actionable error messages. When products_by_affiliate receives an invalid store name, return: '{"error": "affiliate_store_name not found. Available stores: ["Store A", "Store B", "Store C"]}' instead of empty list.
• Standardize error messages to English. The products_detail error message 'Informe product_id ou external_id' breaks consistency; use 'Provide either product_id or external_id, not both.'
• Document mutually exclusive parameters explicitly. Add to products_detail description: 'Either product_id or external_id must be provided (not both).' Add the same to products_by_affiliate.
• Add readOnlyHint tool annotations to the FastMCP registration to signal to clients that all 16 tools are read-only and safe to retry. This enables more aggressive caching and retry logic in agents.