Two tools with basic schemas and minimal descriptions. Both tools have input schemas with proper types (number, string enum), but descriptions are extremely short (10-40 chars) and lack context for LLM selection. No output schema documentation. Error handling is minimal (divide-by-zero check in calculate tool only). Tool names lack action verbs ('add' and 'calculate' are weak; 'perform_addition' and 'perform_calculation' would be clearer). No parameter descriptions beyond type hints. No guidance on when to use one tool vs. the other.

• Expand tool descriptions to 50-200 characters. Example for 'calculate': 'Performs arithmetic operations (add, subtract, multiply, divide) on two numbers. Use this for multi-operation math; use add() for simple addition only.'
• Add descriptions to all parameters. Example: 'operation: The arithmetic operation to perform. Must be one of: add, subtract, multiply, divide.' and 'a: The first operand (any real number).'
• Document the output schema explicitly. Specify that responses return a JSON object with a 'result' field (number) or 'error' field (string) for error cases.
• Remove the redundant 'add' tool. Keep only 'calculate' with operation enum. If a shorthand is needed, rename 'add' to 'quick_add' and document when to use it vs. 'calculate'.
• Add error handling guidance. For divide-by-zero, return a structured error response with a 'code' field (e.g., 'DIVISION_BY_ZERO') and actionable message: 'Cannot divide by zero. Check operands and retry.'