Four basic arithmetic tools with complete input schemas and minimal descriptions. All tools have proper JSON Schema definitions with required fields and type constraints. However, descriptions are extremely terse (10-27 chars), parameter descriptions are entirely absent, and output schemas are undocumented. No error handling guidance, no parameter constraints beyond type, and no indication of idempotency or side effects. The divide tool has a runtime check for division by zero but no description of this constraint. Tools follow verb_noun naming (add, subtract, multiply, divide) which is correct, but descriptions lack context about when to use each tool or what they return.

• Expand tool descriptions to 50-150 characters. Example: 'add: Returns the sum of two numbers. Use when you need to combine numeric values. Parameters a and b must be finite numbers.'
• Add parameter descriptions in the schema. For each of 'a' and 'b', add a description field: 'A finite number to add' or 'The number to subtract from a'. Include valid ranges if applicable.
• Document the output schema in the tool description or as a separate schema field. Clarify that the response contains both text and structured {result: number} fields.
• Add explicit constraint documentation for divide: 'Parameter b must not be zero. If b=0, the tool will return an error: "Cannot divide by zero".'
• Declare tool annotations (idempotentHint: true) in the tool definition to signal to LLMs that these tools are safe to retry and have no side effects.

Inferred effective spec: 2025-06-18+.

• Relies on Stateful initialize / Mcp-Session-Id (removed; protocol is stateless) - make each request self-contained