diff --git a/tests/unit/test_retrieval/test_document_rag_service.py b/tests/unit/test_retrieval/test_document_rag_service.py
new file mode 100644
index 00000000..55b9b97f
--- /dev/null
+++ b/tests/unit/test_retrieval/test_document_rag_service.py
@@ -0,0 +1,77 @@
+"""
+Unit test for DocumentRAG service parameter passing fix.
+Tests that user and collection parameters from the message are correctly
+passed to the DocumentRag.query() method.
+"""
+
+import pytest
+from unittest.mock import MagicMock, AsyncMock, patch
+
+from trustgraph.retrieval.document_rag.rag import Processor
+from trustgraph.schema import DocumentRagQuery, DocumentRagResponse
+
+
+class TestDocumentRagService:
+    """Test DocumentRAG service parameter passing"""
+
+    @patch('trustgraph.retrieval.document_rag.rag.DocumentRag')
+    @pytest.mark.asyncio
+    async def test_user_and_collection_parameters_passed_to_query(self, mock_document_rag_class):
+        """
+        Test that user and collection from message are passed to DocumentRag.query().
+        
+        This is a regression test for the bug where user/collection parameters
+        were ignored, causing wrong collection names like 'd_trustgraph_default_384'
+        instead of 'd_my_user_test_coll_1_384'.
+        """
+        # Setup processor
+        processor = Processor(
+            taskgroup=MagicMock(),
+            id="test-processor",
+            doc_limit=10
+        )
+        
+        # Setup mock DocumentRag instance
+        mock_rag_instance = AsyncMock()
+        mock_document_rag_class.return_value = mock_rag_instance
+        mock_rag_instance.query.return_value = "test response"
+        
+        # Setup message with custom user/collection
+        msg = MagicMock()
+        msg.value.return_value = DocumentRagQuery(
+            query="test query",
+            user="my_user",        # Custom user (not default "trustgraph")  
+            collection="test_coll_1",  # Custom collection (not default "default")
+            doc_limit=5
+        )
+        msg.properties.return_value = {"id": "test-id"}
+        
+        # Setup flow mock
+        consumer = MagicMock()
+        flow = MagicMock()
+        
+        # Mock flow to return AsyncMock for clients and response producer
+        mock_producer = AsyncMock()
+        def flow_router(service_name):
+            if service_name == "response":
+                return mock_producer
+            return AsyncMock()  # embeddings, doc-embeddings, prompt clients
+        flow.side_effect = flow_router
+        
+        # Execute
+        await processor.on_request(msg, consumer, flow)
+        
+        # Verify: DocumentRag.query was called with correct parameters
+        mock_rag_instance.query.assert_called_once_with(
+            "test query",
+            user="my_user",           # Must be from message, not hardcoded default
+            collection="test_coll_1", # Must be from message, not hardcoded default  
+            doc_limit=5
+        )
+        
+        # Verify response was sent
+        mock_producer.send.assert_called_once()
+        sent_response = mock_producer.send.call_args[0][0]
+        assert isinstance(sent_response, DocumentRagResponse)
+        assert sent_response.response == "test response"
+        assert sent_response.error is None
\ No newline at end of file
diff --git a/trustgraph-flow/trustgraph/retrieval/document_rag/rag.py b/trustgraph-flow/trustgraph/retrieval/document_rag/rag.py
index 0cca2cff..2e5149c9 100755
--- a/trustgraph-flow/trustgraph/retrieval/document_rag/rag.py
+++ b/trustgraph-flow/trustgraph/retrieval/document_rag/rag.py
@@ -92,7 +92,12 @@ class Processor(FlowProcessor):
             else:
                 doc_limit = self.doc_limit
 
-            response = await self.rag.query(v.query, doc_limit=doc_limit)
+            response = await self.rag.query(
+                v.query, 
+                user=v.user, 
+                collection=v.collection, 
+                doc_limit=doc_limit
+            )
 
             await flow("response").send(
                 DocumentRagResponse(