mcp-snowflake-server

Instructions

Implementation Reference

• src/mcp_snowflake_server/server.py:53-88 (handler)

  The handler function for the 'list_databases' tool. It queries Snowflake's INFORMATION_SCHEMA.DATABASES, applies optional exclusion filters, and returns results in YAML format with optional JSON embedded resource.
  async def handle_list_databases(arguments, db, *_, exclusion_config=None, exclude_json_results=False): query = "SELECT DATABASE_NAME FROM INFORMATION_SCHEMA.DATABASES" data, data_id = await db.execute_query(query) # Filter out excluded databases if exclusion_config and "databases" in exclusion_config and exclusion_config["databases"]: filtered_data = [] for item in data: db_name = item.get("DATABASE_NAME", "") exclude = False for pattern in exclusion_config["databases"]: if pattern.lower() in db_name.lower(): exclude = True break if not exclude: filtered_data.append(item) data = filtered_data output = { "type": "data", "data_id": data_id, "data": data, } yaml_output = to_yaml(output) json_output = to_json(output) results: list[ResponseType] = [types.TextContent(type="text", text=yaml_output)] if not exclude_json_results: results.append( types.EmbeddedResource( type="resource", resource=types.TextResourceContents( uri=f"data://{data_id}", text=json_output, mimeType="application/json" ), ) ) return results
• src/mcp_snowflake_server/server.py:383-391 (registration)

  Registration of the 'list_databases' tool in the all_tools list, including name, description, input schema, and handler reference.
  Tool( name="list_databases", description="List all available databases in Snowflake", input_schema={ "type": "object", "properties": {}, }, handler=handle_list_databases, ),
• src/mcp_snowflake_server/server.py:386-389 (schema)

  Input schema for 'list_databases': an empty object, indicating no input parameters are required.
  input_schema={ "type": "object", "properties": {}, },
• src/mcp_snowflake_server/server.py:549-558 (helper)

  Special handling in the generic call_tool handler to pass exclusion_config and exclude_json_results specifically to list_databases and similar listing tools.
  if name in ["list_databases", "list_schemas", "list_tables"]: return await handler( arguments, db, write_detector, allow_write, server, exclusion_config=exclusion_config, exclude_json_results=exclude_json_results, )