Single tool 'add' has critical definition gaps. Input schema present with Zod types (a, b as numbers) but parameter descriptions are null, violates the requirement that every parameter needs a description. Tool description is missing entirely (no docstring visible in registration). Output schema not documented. No error handling guidance. Naming is acceptable (verb_noun pattern) but insufficient to overcome missing descriptions and documentation.

• Add a tool description: 'Adds two numbers together and returns the sum. Use this for basic arithmetic operations. Returns the result as a text string.'
• Add parameter descriptions in the Zod schema: z.number().describe('First operand (number to add)') and z.number().describe('Second operand (number to add)')
• Document the output schema: 'Returns an object with a content array containing a single text field with the numeric sum as a string.'
• Add error handling for non-numeric inputs: validate and return a clear error message like 'Invalid input: both a and b must be numbers.'
• Consider expanding the tool set beyond arithmetic, a single 'add' tool is not a useful MCP server. Add multiply, subtract, divide, or other operations to demonstrate real utility.