The EFMS server has 11 tools with basic descriptions, but exhibits significant gaps in schema documentation, parameter validation, and error handling. Most tools lack visible input parameter schemas despite being defined in code. Descriptions are present but often generic or in Vietnamese without English context. Output schemas are not documented. Several tools accept optional parameters without clear constraints. Error handling exists but returns plain strings without structured guidance. No tool annotations (readOnlyHint, destructiveHint, idempotentHint) are present despite the server implementing both read-only and write operations.

• Provide English descriptions (50-200 chars) for all tools following the pattern: 'WHAT it does | WHEN to use it | Any prerequisites'. Example: 'get_departments: Retrieve list of all departments in EFMS. Use before querying cost centers or transactions by department. Requires authentication token.'
• Add explicit JSON Schema input definitions to all tool registrations in mcp_handler.py, including type, description, enum constraints, and min/max for numeric parameters. Example for pagination: {"page": {"type": "integer", "description": "Page number (1-indexed, default 1)", "minimum": 1}, "page_size": {"type": "integer", "description": "Items per page (1-100, default 50)", "minimum": 1, "maximum": 100}}
• Document output schemas as structured examples in tool docstrings or a separate schema file. Specify field names, types, and which fields are required. Example: 'Returns {departments: [{id: UUID, name: string, code: string}], total: integer}'
• Add tool annotations: @mcp.tool(readOnlyHint=True) to read-only tools; @mcp.tool(destructiveHint=True) to update_transaction and process_task_action; @mcp.tool(idempotentHint=True) to safe reads.
• Implement structured error responses with error code, message, and suggested recovery. Example: {'error': 'UNAUTHORIZED', 'message': 'Token invalid or expired', 'recovery': 'Provide a fresh auth token'} instead of plain strings.
• Add SQL injection guards to execute_sql_query: whitelist allowed tables, block DDL/DML, validate query before execution. Or restrict to named queries only.

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

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