Single tool 'calculate' with basic arithmetic operations. While the tool is explicitly registered with a schema and description, the implementation has critical gaps in parameter documentation and error handling patterns. The description is minimal (9 chars in English: 'Execute basic arithmetic operations'), lacks guidance on when to use the tool, and parameters x and y are marked as not required despite being essential for any meaningful calculation. The schema is present and correctly typed, but parameter descriptions are extremely brief and lack format/constraint guidance. Error handling is minimal, only division-by-zero is caught; no guidance for invalid inputs or retry recovery. The tool name 'calculate' is generic and does not follow verb_noun conventions (e.g., 'compute_arithmetic' would be clearer). Output is plain text ('%.2f' formatted), not structured. No pagination, no batching, no chaining IDs. The server supports resources but does not use them. Logging is enabled but no evidence of proper audit trails or permission gates. Overall, this is a minimalist proof-of-concept that would require substantial work to meet production patterns.

• Rename 'calculate' to 'compute_arithmetic' or 'execute_math_operation' to follow verb_noun pattern and improve discoverability.
• Mark parameters 'x' and 'y' as required:true, not false. If optional defaults are desired, document them explicitly: 'Defaults: x=0, y=1' with rationale.
• Expand tool description to 100 - 150 chars explaining what it does, when to use it (e.g., 'Use this to perform basic arithmetic on two numbers'), and what it returns. Example: 'Computes arithmetic results (add, subtract, multiply, divide). Returns decimal result. For division, divisor cannot be zero.'
• Expand parameter descriptions. For 'x' and 'y': 'Numeric operand; can be positive, negative, or decimal.' For 'operation': 'Operation type: add (sum), subtract (difference), multiply (product), divide (quotient; y≠0).'
• Return structured JSON output: {"result": <number>, "operation": <string>, "x": <number>, "y": <number>, "formatted": <string>} instead of plain text. Enables LLMs to extract and chain results more reliably.
• Add input validation before type assertions. Check that x and y are present and are numbers. Return actionable error: 'Missing or invalid parameter: x and y must be numbers. Received: x={}, y={}. Example call: {"operation": "add", "x": 5, "y": 3}' (avoiding example values per pattern:tool-description).
• Add tool annotations via mcp-go if supported: mark as read-only to signal to LLM that this tool has no side effects and is safe to call multiple times.
• Consider supporting batch calculations or advanced operations (power, modulo, square root) if the tool grows. For now, keep it focused on the four basic operations.

Inferred effective spec: <=2025-11-25.

• Relies on Logging (deprecated) - log to stderr or use OpenTelemetry