Flatten rag tool outputs (#1066)

griptape/tools/rag/tool.py

@@ -5,7 +5,7 @@
 from attrs import define, field
 from schema import Literal, Schema
 
-from griptape.artifacts import BaseArtifact, ErrorArtifact, ListArtifact
+from griptape.artifacts import ErrorArtifact, ListArtifact
 from griptape.tools import BaseTool
 from griptape.utils.decorators import activity
 
@@ -31,11 +31,18 @@ class RagTool(BaseTool):
             "schema": Schema({Literal("query", description="A natural language search query"): str}),
         },
     )
-    def search(self, params: dict) -> BaseArtifact:
+    def search(self, params: dict) -> ListArtifact | ErrorArtifact:
         query = params["values"]["query"]
 
         try:
-            outputs = self.rag_engine.process_query(query).outputs
+            artifacts = self.rag_engine.process_query(query).outputs
+
+            outputs = []
+            for artifact in artifacts:
+                if isinstance(artifact, ListArtifact):
+                    outputs.extend(artifact.value)
+                else:
+                    outputs.append(artifact)
 
             if len(outputs) > 0:
                 return ListArtifact(outputs)