Two well-structured tools with complete input schemas, clear descriptions, and proper Pydantic models. Tool names follow verb_noun convention (search_news, get_top_headlines). Descriptions are adequate (100-150 chars). All parameters have types and descriptions. Output schemas are documented via NewsArticle, SearchNewsResponse, TopHeadlinesResponse models. Error handling includes API key validation, rate limit detection, and timeout management with actionable messages. Main gaps: no enum constraints for category/language/country (free-form strings invite hallucination), parameter descriptions reference external docs instead of inline constraints, and no pagination guidance in descriptions despite supporting it.

• Convert category, language, and country parameters to enums with explicit valid values. E.g. category: Literal['general', 'world', 'nation', 'business', 'technology', 'entertainment', 'sports', 'science', 'health'].
• Add inline constraint descriptions: 'Language code (ISO 639-1: en, es, fr, de, it, pt, ru, ar, zh, ja, ko, etc.)' instead of 'See docs for full list.'
• Update tool descriptions to mention pagination: 'Supports pagination via page parameter. Use page=2, page=3, etc. to retrieve additional results.'
• Document the GNEWS_API_KEY prerequisite in tool descriptions: 'Requires GNEWS_API_KEY environment variable to be set on the server.'
• Add tool annotations via @mcp.tool decorator: readOnlyHint=True, idempotentHint=True for both tools to signal safe retry semantics.