The server demonstrates solid foundation with 12 well-named tools covering a coherent legal research domain. All tools have clear, action-verb names (semantic_search, keyword_search, get_case, etc.) and descriptions are present and meaningful (avg ~120 chars). Input schemas are comprehensively defined using Pydantic models with proper types, constraints, and descriptions. However, output schemas are entirely undocumented, the code shows Pydantic input models but provides no schema definition for what each tool returns. This is a critical gap that prevents LLMs from understanding response structure. Additionally, error handling is minimal; there's no evidence of actionable recovery guidance or error categorization. The server lacks tool annotations (readOnlyHint, destructiveHint) despite all tools being read-only, which is a missed opportunity for clarity. Date parameters use proper regex patterns, limits are enforced (1-100 for most), and response format enums are present, but the overall absence of output documentation and error patterns costs the score significantly.

• Document output schemas for all tools. For each tool, add a response example and schema. E.g., semantic_search should return: { results: [ { cluster_id: int, case_name: str, date_filed: str, court: str, opinion_summary: str } ], total_count: int, has_more: bool }
• Add try-catch blocks with actionable error messages. When api_client throws CourtListenerAPIError, catch it and return: { error: 'Court ID not found: scotus-invalid. Valid courts: scotus, ca9, tenn, ...', retry: true }
• Add readOnlyHint=true to all tool definitions via FastMCP's tool decorator. This signals to agents that these tools are safe to call without destructive side effects.
• Clarify response_format behavior. Add implementation that actually produces markdown tables for search results and JSON objects for individual cases. Document field mappings in each tool's description.
• Implement pagination for search tools. Add next_cursor or page_token to results when results exceed limit. Add a note in tool descriptions: 'Returns up to {limit} results. Use pagination_token to fetch additional results.'
• Add per-parameter validation and helpful error messages. E.g., for date_after/date_before, validate regex match and return 'Invalid date format. Expected YYYY-MM-DD, got 2024/01/15' instead of letting it fail silently.
• Document which fields are guaranteed in responses. E.g., get_case should guarantee: cluster_id, case_name, date_filed, court_id. Optional fields (judges, citations_count) should be marked as such.
• Add examples of common queries to tool descriptions. E.g., semantic_search: 'Example: "disability discrimination in hiring" finds ADA employment cases. Use keyword_search for precise Boolean queries like "disability AND hiring AND retaliation".'