Input schemas are present but extremely sparse: only a single 'city'/'username' parameter with minimal type info and no validation constraints. No output schemas documented. No error handling guidance. Tool names follow verb_noun pattern but descriptions lack WHAT/WHEN/WHY context required for LLM selection. No parameter constraints (enums, ranges, formats). Composition is reasonable (two independent tools) but definitions are production-unready.

• Expand tool descriptions to 50-200 chars. Example for get-weather-forecast: 'Fetch current weather forecast for a city. Returns temperature, humidity, wind speed, and 7-day outlook. Requires city name (e.g., Beijing, Shanghai). Returns error if city not found, try search_cities() first.'
• Add parameter constraints: city should accept string 1-100 chars (no special chars); username should accept alphanumeric + hyphens, 1-39 chars (GitHub username rules). Document these in parameter descriptions.
• Document output schema for each tool. Example: get-weather-forecast returns {city: string, temperature: number, humidity: number, wind_speed: number, forecast: [{date: string, high: number, low: number}]}.
• Add error handling: 'If city not found, return error with message: "City '{city}' not found. Try search_cities() with partial name." If API timeout, return retryable error with guidance to retry in 5 seconds.'
• Clarify parameter optionality: if 'city' is truly optional, document the default behavior (e.g., 'Defaults to user's current location if omitted'). If required, remove '(optional)' marker.