Single tool 'add' with basic schema and minimal documentation. Tool is clearly named (verb_noun pattern) and has a valid input schema with type definitions, but lacks depth in descriptions. The tool description is only 29 characters ('Adds two numbers together'), which falls below the recommended 50-200 character range for LLM optimization. Parameter descriptions exist but are minimal (13 chars for 'a', 12 chars for 'b'). No output schema is documented. No error handling guidance, recovery patterns, or context about when/why to use this tool. The implementation via Zod schema is correct, but the metadata layer is sparse for production use.

• Expand tool description to 80-150 chars: 'Adds two numbers together and returns the sum. Use this for arithmetic operations on numeric values. Returns the result as text (e.g., '5' for 2+3). Note: very large numbers may lose precision.'
• Add parameter constraints to descriptions: Change 'a' description to 'First number to add (numeric value, supports integers and decimals)' and 'b' to 'Second number to add (numeric value, supports integers and decimals)'.
• Document the output schema in tool description: 'Returns: text/plain string containing the numeric sum (e.g., "5"). No error handling is performed, invalid inputs will cause tool failure.'
• Add error handling and guidance: If Zod validation fails, return a clear error message like 'Invalid input: both a and b must be numeric values (received a=<actual> [type], b=<actual> [type]). Please provide valid numbers.'
• Consider adding bounds/constraints to parameter descriptions if this tool is meant for specific use cases (e.g. 'valid range: -1e15 to 1e15 to avoid floating-point precision loss').