Basic Math Calculator has clear, simple tool definitions with proper schemas and descriptions. All 4 tools (add, subtract, multiply, divide) have input schemas with typed parameters (float) and descriptions. However, the server exhibits significant gaps in production-readiness patterns: no error handling guidance (divide returns a string error instead of structured error), no output schemas documented, no parameter constraints (e.g., divide should validate denominator != 0 before execution), and descriptions are minimal (10-50 chars, below the 50-200 char baseline for LLM-optimized tools). The divide tool returns inconsistent types (str vs float), violating the structured output pattern. No tool annotations, no idempotency hints, no permission gates. This is a toy implementation suitable for learning but not production use.

• Document output schemas for all tools. Add to each tool docstring: 'Returns: float (the result of the operation)' or use a structured return type hint.
• Refactor divide() to return a consistent type. Either return float and raise an exception on division by zero, or return a structured object {result: float | null, error: string | null}.
• Expand tool descriptions to 80-150 characters. Example: 'Add two numbers together. Returns the sum as a float. Use this for basic arithmetic operations. Accepts any float values.'
• Add tool annotations via FastMCP. Mark all tools with readOnlyHint=true and idempotentHint=true so agents know they are safe to retry.
• Add input validation and structured error responses. Validate that a and b are finite numbers; return {error: 'INVALID_INPUT', message: 'a must be a finite number', recovery: 'Provide a valid float'} instead of string errors.