This MCP server has 2 tools with basic schemas and descriptions, but significant quality gaps prevent a higher score. Both tools have descriptions and input schemas present, but descriptions are terse (both under 100 chars), parameter descriptions lack detail, and there is no documented output schema. Error handling is minimal, tools return plain strings without guidance for recovery. The tool names follow verb_noun convention ('search_papers', 'extract_info') but are somewhat generic. No tool annotations (readOnlyHint, destructiveHint, idempotentHint) are present. The 'search_papers' tool modifies state (writes to disk) but this is not clearly stated in the description. Parameter constraints (e.g., max_results range) are absent from descriptions. Output is unstructured text rather than typed JSON objects, making it difficult for LLMs to extract specific fields for downstream tool chaining. This server lands in the 'Fair' range, functional but not production-ready.

• Add formal output schema documentation to both tools. For search_papers: return {"papers": [{"id": string, "title": string, "authors": [string], "summary": string, "pdf_url": string, "published": string}], "count": int}. For extract_info: return {"paper_id": string, "title": string, "authors": [string], "summary": string, "pdf_url": string, "published": string}.
• Expand search_papers description to explicitly state side effects: 'Searches arXiv for papers matching a topic and stores metadata (title, authors, summary, PDF URL, publication date) in JSON files within the papers/ directory, organized by topic. Returns a list of paper IDs that can be passed to extract_info.'
• Add parameter constraints to search_papers: 'max_results: int, 1-100, default 5. Maximum number of papers to retrieve from arXiv. Higher values return more results but take longer.'
• Add recovery guidance to error messages. When extract_info returns 'No information found...', append 'Try calling search_papers() with a relevant topic to index papers first.'
• Add tool annotations: readOnlyHint=true for extract_info, destructiveHint=true for search_papers (because it writes to disk).
• Return structured JSON objects instead of comma-separated strings. Modify execute_tool() to return typed dictionaries, not plain text.
• Add pagination support to search_papers if future improvements allow querying beyond max_results=5. Return {"papers": [...], "total": int, "page": int, "page_size": int}.
• Add parameter to specify output format (JSON, markdown summary) or target topic for extracted_info to enable richer downstream uses.