Single tool 'add' has a valid schema with typed parameters (a, b as numbers) but critical gaps prevent higher scoring. Tool description is minimal (10 chars) and lacks context on when/why to use it. No output schema documented. No error handling guidance. The tool is trivial (arithmetic) but the definition quality is below production baseline.

• Add non-empty descriptions to both 'a' and 'b' parameters. Example: 'a: The first number (numeric value)' and 'b: The second number (numeric value)'. Minimum 10 chars each.
• Expand tool description to 50-200 chars. Example: 'Adds two numbers together and returns the sum. Use this when you need to perform basic arithmetic calculations. Returns the numeric result as text.'
• Document the output schema explicitly. Clarify that the tool returns a text response containing the numeric sum.
• Rename tool from 'add' to 'calculate_sum' or 'add_numbers' to follow verb_noun convention and improve LLM discoverability.
• Add input validation and error handling. Return structured errors like 'Invalid input: a and b must be numbers. Got a={type(a)}, b={type(b)}' instead of silent failures.