Single tool 'add' has a clear, concise description (28 chars) and properly typed input schema with parameter descriptions. However, the description is below the 50-200 char baseline for LLM-optimized descriptions, lacks context on when/why to use it, and provides no output schema documentation. No error handling guidance. Tool is trivial (arithmetic) but definition gaps prevent higher scoring.

• Expand tool description to 80-150 chars: 'Adds two numbers together and returns the sum. Use this for arithmetic calculations. Returns a text representation of the result.'
• Document output schema explicitly: 'Returns {content: [{type: "text", text: string}]} where text is the numeric sum as a string.'
• Add error handling: 'If inputs are not numbers, returns error: "Invalid input: both a and b must be numbers."'
• Consider renaming to 'add_numbers' for clarity in tool discovery and multi-tool agent scenarios.
• Add parameter constraints to descriptions: 'a: First number to add (any finite number)' and 'b: Second number to add (any finite number)'.