Two tools with minimal descriptions and basic schemas. 'add' (18 chars) and 'calculate' (40 chars) descriptions fall below the 50-200 char LLM-optimized baseline. Both tools lack parameter descriptions entirely, critical gap per pattern:tool-description. Schemas are present but sparse: no min/max bounds, no format hints, no error guidance. No output schema documented. Tools are simple arithmetic operations with no composition risk, but lack the clarity and completeness expected of production tools.

• Add parameter descriptions to both tools: 'a: First operand (number, range: -1e6 to 1e6)' and 'b: Second operand (number, range: -1e6 to 1e6)'. Specify valid ranges to prevent overflow.
• Expand tool descriptions to 80-150 chars. Example for 'add': 'Adds two numbers and returns the sum. Use this for simple addition; use calculate() for subtract, multiply, or divide operations.' This clarifies when to pick each tool.
• Document output schema explicitly. Example: 'Returns {result: number}, the arithmetic result as a JSON number.'
• For 'calculate', return structured error on division by zero: {error: 'division_by_zero', message: 'Cannot divide by zero. Check operand b and retry with a non-zero value.', retryable: true} instead of plain text.
• Add enum constraint to 'operation' parameter description: 'The arithmetic operation: one of add, subtract, multiply, divide. Divide by zero returns an error.'