list_objects
Retrieve a list of objects, such as tables, views, sequences, or extensions, within a specified schema using this tool. Streamline schema exploration and data management for Postgres MCP workflows.
Instructions
List objects in a schema
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| object_type | No | Object type: 'table', 'view', 'sequence', or 'extension' | table |
| schema_name | Yes | Schema name |
Implementation Reference
- src/postgres_mcp/server.py:109-175 (handler)The main handler function for the 'list_objects' tool. It lists database objects (tables, views, sequences, or extensions) in a specified schema by executing appropriate SQL queries against information_schema and pg_extension. The function is decorated with @mcp.tool, which also serves as registration. Input schema is defined inline using Pydantic Field.
@mcp.tool(description="List objects in a schema") async def list_objects( schema_name: str = Field(description="Schema name"), object_type: str = Field(description="Object type: 'table', 'view', 'sequence', or 'extension'", default="table"), ) -> ResponseType: """List objects of a given type in a schema.""" try: sql_driver = await get_sql_driver() if object_type in ("table", "view"): table_type = "BASE TABLE" if object_type == "table" else "VIEW" rows = await SafeSqlDriver.execute_param_query( sql_driver, """ SELECT table_schema, table_name, table_type FROM information_schema.tables WHERE table_schema = {} AND table_type = {} ORDER BY table_name """, [schema_name, table_type], ) objects = ( [{"schema": row.cells["table_schema"], "name": row.cells["table_name"], "type": row.cells["table_type"]} for row in rows] if rows else [] ) elif object_type == "sequence": rows = await SafeSqlDriver.execute_param_query( sql_driver, """ SELECT sequence_schema, sequence_name, data_type FROM information_schema.sequences WHERE sequence_schema = {} ORDER BY sequence_name """, [schema_name], ) objects = ( [{"schema": row.cells["sequence_schema"], "name": row.cells["sequence_name"], "data_type": row.cells["data_type"]} for row in rows] if rows else [] ) elif object_type == "extension": # Extensions are not schema-specific rows = await sql_driver.execute_query( """ SELECT extname, extversion, extrelocatable FROM pg_extension ORDER BY extname """ ) objects = ( [{"name": row.cells["extname"], "version": row.cells["extversion"], "relocatable": row.cells["extrelocatable"]} for row in rows] if rows else [] ) else: return format_error_response(f"Unsupported object type: {object_type}") return format_text_response(objects) except Exception as e: logger.error(f"Error listing objects: {e}") return format_error_response(str(e))