Server has 4 tools with basic descriptions but critical gaps in schema completeness, parameter documentation, and error handling. Two tools (execute_sql_query, query_data) appear to be duplicates with identical descriptions. Input schemas are minimal, only 'sql' and 'tables' parameters visible with type strings but no constraints, ranges, or validation guidance. No output schemas documented. Descriptions are generic (10-50 chars) and lack context on when to use each tool or what they return. No error handling guidance, no security validation details, and no idempotency guarantees despite WRITE risk on execute_sql_query.

• Remove query_data or rename it with a distinct purpose (e.g., query_data_read_only if it enforces SELECT-only). Document the difference from execute_sql_query in both descriptions.
• Add output schemas for all tools. Example for list_database_tables: {type: 'object', properties: {tables: {type: 'array', items: {type: 'string'}}, total_count: {type: 'integer'}}}.
• Expand descriptions to 100-200 chars. For execute_sql_query: 'Execute SQL queries on the salaries database. Supports SELECT, INSERT, UPDATE. Returns result rows or affected row count. Use query_data for read-only queries.'
• Add SQL parameter constraints: description should state 'SQL query string. Allowed: SELECT, INSERT, UPDATE. Forbidden: DROP, DELETE, ALTER. Max 5000 chars. Queries are executed with read-write permissions.'
• Add error recovery hints. Example: 'If table not found, call list_database_tables() to see available tables. If syntax error, check column names with get_table_info(table_name).'