The server exposes a single tool 'add' with minimal but complete definition. The tool name is clear and verb-based (good), the description is present and adequate (10-word minimum met), and the input schema is properly typed using Zod. However, the description is quite terse (23 chars, below the 50-200 char ideal for LLM selection), parameter descriptions are minimal (single noun phrases), and there is no output schema documentation. The server lacks sophistication in error handling, result shaping, and guidance on when to use the tool vs alternatives. For a single arithmetic operation, this is acceptable as a demo, but it does not meet production baseline expectations. The implementation is straightforward and correct, but minimal.

• Expand 'add' description to 50-150 chars: 'Adds two numbers and returns their sum. Supports integers and floats. Returns the result as a numeric value.' This provides LLM context for selection and usage.
• Document parameter constraints: 'a' → 'First number to add (integer or float, within JavaScript safe integer range -2^53+1 to 2^53-1)'; 'b' → 'Second number to add (same constraints as a)'.
• Explicitly document output: 'Returns an object with a single text field containing the numeric sum, e.g., {"content": [{"type": "text", "text": "42"}]}'.
• Add error handling: 'If inputs are NaN or Infinity, return an error message describing the constraint violation (e.g., "Input 'a' is NaN, provide a valid number").' This guides the LLM to self-correct.