The server defines 3 tools with varying quality. search_subsidies has a detailed, lengthy description (1000+ chars) with good parameter documentation and clear constraints from the jGrants API. However, descriptions are overly verbose for LLM consumption (exceed 1024 char guidance), parameters lack proper type definitions in schema (missing 'type' fields), and the ping tool is a legacy pattern. The get_subsidy_overview tool has a moderate description but also lacks formal parameter schemas. Error handling is basic (returns {error: ...} dict) with minimal guidance for recovery. No tool annotations (readOnlyHint, destructiveHint) are present. The codebase shows path traversal protection and HTTP timeout handling, which is good for security, but parameter validation is minimal and no confirmation patterns for destructive ops exist.

• Refactor search_subsidies description to ~150 chars: 'Search for subsidies by keyword, industry, location, and other criteria. Returns up to N results ranked by acceptance deadline.' Move enumerated valid values to formal schema enums (use_purpose, industry, target_number_of_employees, target_area_search).
• Add formal JSON Schema to all tools via @mcp.tool() parameters. Define type: 'string', enum: [...] for constrained parameters. Example: use_purpose enum should list all 16 valid values from the jGrants API docs.
• Remove the ping tool entirely. It is deprecated in MCP spec 2026-07-28 and provides no value for LLM agents.
• Enhance error responses with recovery paths. Instead of 'エラーが発生しました', return: '{"error": "Timeout calling jGrants API after 30s. Retry in 5 seconds or try a simpler keyword."}', tells the agent what happened and what to try next.
• Add tool annotations via @mcp.tool(readOnlyHint=true) for all three tools (all are read-only). This signals safety to agents and enables aggressive retries.
• Document output schemas explicitly. For search_subsidies, return a typed response object with subsidy[] (each with id, name, acceptance_end_datetime, subsidy_max_limit, etc.), total_count: int, and search_conditions: object.
• Add pagination support to search_subsidies if the jGrants API supports it (limit/offset or cursor). Current implementation returns all results, which can blow the context window. Indicate max result size (e.g., 'Returns up to 100 subsidies') in the description.

Inferred effective spec: <=2025-11-25.

• Relies on Logging (deprecated) - log to stderr or use OpenTelemetry