Single tool with adequate but incomplete quality. Tool name 'RAG tool' lacks action verb and is generic; description is present but minimal (94 chars, below baseline avg of 194 chars). Input schema is properly defined with type and description, but output schema is undocumented, LLM cannot anticipate response structure. No error handling guidance, no parameter constraints, no security annotations. Tool is READ_ONLY (good) but lacks actionable error recovery patterns. This is typical C-grade community server territory.

• Rename tool to 'search_documents' or 'retrieve_documents' to convey action to LLM
• Expand description to 150-250 chars: explain WHEN to use (user has a question about documents), WHAT is returned (ranked document excerpts with relevance scores), and any prerequisites (documents must be indexed first)
• Document output schema explicitly in tool definition or description: 'Returns array of {score: float, file: string, text: string}. Score 0.0 - 1.0 indicates relevance.'
• Add error recovery guidance: catch retriever errors and return 'Document retrieval failed: [reason]. Check if indexing is complete and try a simpler query.' for pattern:recovery-guide
• Add limit and offset parameters (default limit=20, max=100) with pagination to prevent context explosion. Document total_results in response.
• Add query format guidance to parameter description: 'Natural language question or keyword search. Minimum 3 characters.'
• Add tool annotation for readOnlyHint (no side effects), since search is read-only per spec. This will help LLM plan tool order.