Web Search Neo demonstrates solid tool definition quality with complete input schemas, clear descriptions, and thoughtful parameter design. All 6 tools have explicit JSON Schema definitions with proper types and descriptions. Tool names follow verb_noun conventions (fetch_*, search_*, get_*). Descriptions are detailed and context-aware, averaging ~150-200 characters. However, output schemas are not formally documented, the server returns results but LLM context about response structure must be inferred. Security considerations (file path confinement, timeout caps, overwrite safeguards) are well-designed. Error handling is implicit but not explicitly guided (no recovery suggestions in descriptions). Tool composition is solid: each tool has a single, clear responsibility, and parameters are well-constrained with enums and defaults.

• Document output schemas explicitly. For each tool, add a 'Returns' section to the description (or a structured returnSchema in the tool definition if your framework supports it). Example for fetch_url_text: 'Returns {text: string, length: integer, url: string, error?: string}'.
• Expand fetch_page_links description to ~100 chars. Explain: 'Extracts and deduplicates absolute hyperlinks from an HTML page. Returns up to `limit` URLs (default 500), useful for crawling discovery or link analysis.'
• Add error recovery guidance to search_web. Example: 'If a search engine is blocked (4xx/5xx), the tool auto-falls back to another engine if fallback=true. Set challenge_mode="manual" to handle CAPTCHA interactively (waits up to manual_timeout_seconds).' This tells LLMs exactly what to expect.
• Tighten the 'headers' parameter description. Add: 'Custom HTTP headers as key-value pairs. Avoid Authorization or User-Agent headers; they are managed server-side.' Prevents LLMs from attempting credential injection.
• Add minimum/maximum constraints to numeric parameters in schema definitions. For timeout_seconds, use {type: number, minimum: 1, maximum: 120}. For max_chars, use {type: integer, minimum: 100, maximum: 1000000}. This makes constraints machine-parseable and reduces ambiguity.
• For fetch_urls_text, clarify the batch behavior in the description: 'Fetches up to 16 pages in parallel. Returns an array of results, one per input URL. If a URL fails, that result contains an error field instead of text. This tool never blocks on individual failures.'