PaperMCP has two clearly defined tools with complete input schemas and reasonable descriptions. Both tools follow verb-noun naming conventions (papers.search, papers.analyze) and are actionable. However, there are notable gaps: output schemas are not documented in the tool definitions, parameter descriptions lack depth and constraint details, and error handling is basic. The server demonstrates partial adherence to Arcade patterns but falls short of production-grade quality.

• Provide English descriptions for both tools. Rewrite descriptions to be 50-200 characters and include WHAT the tool does, WHEN to use it, and any prerequisites. Example: 'papers.search: Search academic papers on arXiv by keyword, author, year, or field. Use this to discover papers before analyzing them. Returns paginated results with title, authors, year, and URL.'
• Document output schemas explicitly in tool definitions. Add an 'output' or 'returns' field (or narrative description) that specifies field names, types, and semantics. Example for papers.search: 'Returns an object with keys: papers (array of {title, authors, year, arxiv_id, url}), total_count (number), page (number), next_page (number or null).'
• Expand parameter descriptions to include constraints, defaults, and error guidance. Example: 'page_size: Integer, minimum 1, maximum 100 (default: 20). Controls how many results per page. If not provided, defaults to 20. Must be a positive integer.'
• Add error recovery guidance. When errors occur (network timeout, PDF too large, unsupported format), return a message that tells the LLM what to try next. Example: 'PDF exceeds 25MB limit. Try: (1) fetch abstract via arXiv API instead, (2) request a smaller portion of the paper, or (3) use a different source.'
• Document default values for optional parameters in the schema descriptions. State 'default: false' or 'default: 5000' explicitly so LLMs understand what happens if the parameter is omitted.
• Add validation error messages that are actionable. Current error 'Failed to fetch PDF: 404' should be 'PDF not found at the provided URL. Check the URL is accessible without authentication. Alternatively, try papers.search to find the paper on arXiv.'