fix(bedrock): skip passthrough output write-back when guardrail returns no texts

litellm/llms/bedrock/passthrough/guardrail_translation/handler.py

@@ -497,6 +497,7 @@ class BedrockPassthroughGuardrailHandler(BaseTranslation):
         )
 
         guardrailed_texts = guardrailed_inputs.get("texts", [])
-        _write_back_texts(guardrailed_texts, holders)
+        if guardrailed_texts:
+            _write_back_texts(guardrailed_texts, holders)
 
         return response

tests/test_litellm/llms/bedrock/passthrough/guardrail_translation/test_handler.py

@@ -597,6 +597,25 @@ class TestBedrockPassthroughGuardrailHandlerOutput:
         assert result["output"]["message"]["content"][0]["text"] == "[MASKED]"
         assert result["stopReason"] == "end_turn"
 
+    @pytest.mark.asyncio
+    async def test_response_guardrail_returning_no_texts_preserves_output(self, monkeypatch):
+        """A guardrail that returns no texts must leave the response untouched and
+        not warn, mirroring the request path's empty-result guard."""
+        handler = BedrockPassthroughGuardrailHandler()
+        response = self._converse_response("Model reply")
+        guardrail = _make_guardrail({"texts": []})
+
+        warnings = []
+        monkeypatch.setattr(
+            "litellm.llms.bedrock.passthrough.guardrail_translation.handler.verbose_proxy_logger.warning",
+            lambda *args, **kwargs: warnings.append(args),
+        )
+
+        result = await handler.process_output_response(response=response, guardrail_to_apply=guardrail)
+
+        assert not warnings
+        assert result["output"]["message"]["content"][0]["text"] == "Model reply"
+
     @pytest.mark.asyncio
     async def test_response_reasoning_and_tooluse_extracted_and_masked(self):
         """Model output hidden in reasoningContent.reasoningText.text and