This server implements two basic calculator tools with proper JSON Schema definitions and reasonable descriptions. Both tools have valid input schemas with typed parameters and enums where appropriate. Descriptions are present but generic ('Simple addition tool', 'Calculator tool with multiple operations'). Parameter descriptions are adequate. However, the tools lack output schema documentation, error recovery guidance, and the descriptions don't explain WHEN to use each tool or distinguish why both exist. No tool annotations (readOnlyHint, etc.) are present. The divide-by-zero error handling in 'calculate' is basic, returns error text but doesn't guide the LLM on recovery. Overall, definitions are competent but lack the depth and LLM-optimization needed for higher production readiness.

• Expand tool descriptions to 80 - 150 characters explaining WHEN to use each tool. Example for 'add': 'Quickly add two numbers. Use this for simple arithmetic; use calculate() for subtract, multiply, divide.' This disambiguates tool selection.
• Document output schema explicitly in tool descriptions or as a separate schema field. Example: 'Returns: {result: number}'. Let LLMs know what fields to expect in the response.
• Add tool annotations to the schema. Mark both tools with readOnlyHint: true since they don't modify state. This signals to agents that these calls are safe to retry.
• Improve error messages in 'calculate' division handler. Change 'Error: Cannot divide by zero' to 'Error: Cannot divide by zero. Use non-zero divisor (b parameter).' This guides the LLM toward correction.
• Consider consolidating 'add' and 'calculate' into a single 'calculate' tool if 'add' is truly just a convenience wrapper. If you keep both, explain the distinction: 'Use add() for fast two-number addition; use calculate() when you need other operations.' This prevents LLM confusion.
• Add parameter descriptions that clarify edge cases. For 'calculate', clarify: 'b: The second number. Must be non-zero for divide operation.' This prevents invalid inputs upfront.