Single tool with basic schema and minimal description. Tool name 'get-weather' follows verb_noun convention (+), but description is only 56 chars and lacks context on when/why to use it. Input schema is present with proper JSON Schema structure, but parameter description is generic. No output schema documented. No error handling guidance. No parameter constraints (e.g., city format, length limits). Tool lacks idempotency hints and does not document API dependencies or failure modes.

• Expand tool description to 100 - 200 chars: 'Fetches current weather for a city. Returns temperature in Celsius. Requires WEATHER_API_KEY env var. Call this to answer questions about current conditions, temperature, or weather status.'
• Document output schema in code comments or a separate schema definition: {type: 'object', properties: {temperature_c: {type: 'number'}, city: {type: 'string'}, ...}, required: [...]}'
• Add parameter constraints: city should be a non-empty string, 2 - 100 chars, alphanumeric + spaces. Document: 'City name (2 - 100 chars, e.g., Istanbul, New York). Must be a valid city.'
• Replace generic error handling with actionable messages: 'City not found. Check spelling or try a larger city name.' or 'API key missing or invalid. Verify WEATHER_API_KEY environment variable is set.'
• Add tool annotation hints (if using MCP 2026-07-28+): mark as readOnlyHint=true and idempotentHint=true to signal to LLMs that repeated calls are safe.