Update tools/sql_tool.py

tools/sql_tool.py

@@ -20,11 +20,25 @@ class SQLTool:
                 eval(key_json) if key_json.strip().startswith("{") else {}
             )
             self.client = bigquery.Client(credentials=creds, project=cfg.gcp_project)
-        elif self.backend == "motherduck":
-            import duckdb
-            token = self.cfg.motherduck_token or os.getenv("MOTHERDUCK_TOKEN")
-            db_name = self.cfg.motherduck_db or "default"
-            self.client = duckdb.connect(f"md:/{db_name}?motherduck_token={token}")
+            elif self.backend == "motherduck":
+                import duckdb
+                token = self.cfg.motherduck_token or os.getenv("MOTHERDUCK_TOKEN")
+                db_name = self.cfg.motherduck_db or "default"
+            
+                # Start a plain DuckDB connection
+                self.client = duckdb.connect()
+            
+                # Ensure the MotherDuck extension is available and loaded
+                # (DuckDB will download it automatically in this environment)
+                self.client.execute("INSTALL motherduck;")
+                self.client.execute("LOAD motherduck;")
+            
+                # Provide token and attach the remote MotherDuck database as 'md'
+                if not token:
+                    raise RuntimeError("Missing MOTHERDUCK_TOKEN")
+                self.client.execute(f"SET motherduck_token='{token}';")
+                self.client.execute(f"ATTACH 'md:/{db_name}' AS md;")
+                self.client.execute("USE md;")  # subsequent queries run against 'md' by default
         else:
             raise RuntimeError("Unknown SQL backend")