The server has 5 tools with basic structure but significant gaps in production quality. Tools are named with verbs and most have descriptions, but descriptions are generic and lack LLM-optimization. Input schemas use Zod with some constraints (min/max), but output schemas are undocumented. Error handling is absent, no guidance on failures, retries, or recovery paths. The 'echo' tool appears to be a test utility and should not be in production. No tool annotations, no pagination guidance, no mention of when tools modify state vs. read-only operations (though Risk fields indicate all are READ_ONLY). Composition is reasonable (each tool does one thing), but the overall package lacks the rigor expected of production-grade tools.

• Add formal output schemas to each tool in the MCP tool registration (not just in the code comment). E.g., for get_total_sales: 'Returns {region: string, totalRevenue: number}'.
• Expand descriptions to 100-150 chars. Include what the tool does, when to use it, and what it returns. Example: 'Get total sales revenue across all records. Use to answer high-level revenue questions. Returns total in USD. Optionally filter by region (e.g., "North America", "EMEA").'
• Add error handling with recovery guidance. Wrap readSales() and handle file-not-found, parse errors, and data validation failures. Return structured error responses like {error: 'CSV file not found', recovery: 'Verify sales.csv exists in data/'}.
• Remove the echo tool from src/test.ts. It is not a business tool and clutters the server definition.
• Add tool annotations to the server.tool() calls. Use .readOnlyHint(true) or similar MCP SDK methods to mark tools as read-only and idempotent.
• Enhance parameter descriptions. For 'limit' parameters, clarify: 'Maximum number of products to return (1-50, defaults to 5). Products are sorted by total revenue descending.' Add tie-breaking rules if applicable.
• Document the output shape of each tool. Add a comment or doc string to the tool registration that shows sample JSON output, e.g., {"region": "North America", "totalRevenue": 50000}.
• Consider adding a get_sales_by_date_range tool to allow time-based filtering, as current tools do not support date constraints.
• Add input validation: validate region names against known regions; validate limit is in [1, 50]. Return actionable error messages on invalid input.