Single tool server with a straightforward arithmetic calculator. The tool has a clear, action-oriented name ('calculate') and a concise description. Input schema is properly defined with type 'object' and a required 'expression' parameter. However, the parameter description is minimal (uses an informal 'e.g.' example rather than formal constraints), and there is no documented output schema. The tool lacks error handling guidance, which is critical for an arithmetic evaluator that will encounter invalid expressions. No tool annotations (readOnlyHint, etc.) despite being READ_ONLY. Overall definition is functional but sparse, typical of starter scaffold code.

• Add an explicit output schema to the tool definition: {"type": "object", "properties": {"result": {"type": "number", "description": "The evaluated result of the expression"}, "error": {"type": "string", "description": "If evaluation failed, an error message explaining why"}}, "required": ["result"] or ["error"]}
• Expand parameter description to: 'A valid Python arithmetic expression string. Supported operators: + (add), - (subtract), * (multiply), / (divide), ** (exponentiate), % (modulo). Example: "(5 + 3) ** 2" evaluates to 64. Invalid syntax or math errors (e.g., division by zero) will return an error.'
• Add tool annotation to schema: include 'readOnlyHint': true at tool definition level to signal the operation is safe/read-only
• Document behavior on edge cases in description: 'Division by zero, invalid syntax, and extremely large exponents will return descriptive errors.'
• Consider adding a 'max_complexity' or similar internal validation to prevent DOS via deeply nested expressions