fix(proxy): keep the model-group alias through vector store credential merges

litellm/proxy/openai_files_endpoints/common_utils.py

@@ -453,6 +453,7 @@ def prepare_data_with_credentials(
     credentials: dict,
     file_id: str | None = None,
     include_internal_credentials: bool = False,
+    routing_model: str | None = None,
 ) -> None:
     """
     Update data dictionary with model credentials (in-place).
@@ -463,8 +464,17 @@ def prepare_data_with_credentials(
         file_id: Optional original file_id to set (for decoded file IDs)
         include_internal_credentials: Preserve an immutable server-side snapshot
             for code paths that must distinguish proxy config from request params.
+        routing_model: Model-group alias to keep in ``data["model"]`` after the
+            merge. Credentials carry the deployment's underlying
+            ``litellm_params.model`` (which call sites dispatching straight to
+            the provider SDK need), but router-bound call sites must keep
+            routing by alias: the underlying model loses the model-group
+            identity (access groups, team scoping) when several aliases share
+            one provider model (#36103).
     """
     data.update(credentials)
+    if routing_model is not None:
+        data["model"] = routing_model
     if include_internal_credentials:
         data["_litellm_internal_model_credentials"] = MappingProxyType(dict(credentials))
     data.pop("custom_llm_provider", None)

litellm/proxy/vector_store_files_endpoints/endpoints.py

@@ -108,6 +108,7 @@ def _update_request_data_with_managed_file_id(
                             data=data,
                             credentials=credentials,
                             file_id=llm_output_file_id,  # Use the actual provider file ID
+                            routing_model=routing_model,
                         )
                         verbose_logger.info(
                             "Routing vector store file operation to model: %s, file_id: %s -> %s",
@@ -272,6 +273,7 @@ async def _update_request_data_with_model_routing_hint(
         prepare_data_with_credentials(
             data=data,
             credentials=credentials,
+            routing_model=model_hint if isinstance(model_hint, str) else None,
         )
         return data
 
@@ -293,6 +295,7 @@ async def _update_request_data_with_model_routing_hint(
         model_names_to_check.append(model_name)
 
     openai_credentials = None
+    openai_model_name = None
     for model_name in model_names_to_check:
         credentials = llm_router.get_deployment_credentials_with_provider(model_id=model_name, team_id=caller_team_id)
         if credentials is None:
@@ -313,9 +316,10 @@ async def _update_request_data_with_model_routing_hint(
         if openai_credentials is not None:
             return data
         openai_credentials = credentials
+        openai_model_name = model_name
 
     if openai_credentials is not None:
-        prepare_data_with_credentials(data=data, credentials=openai_credentials)
+        prepare_data_with_credentials(data=data, credentials=openai_credentials, routing_model=openai_model_name)
     elif len(model_names_to_check) == 1:
         await _authorize_model_routing_hint(
             model=model_names_to_check[0],

tests/test_litellm/proxy/test_model_based_routing_files_batches.py

@@ -88,6 +88,40 @@ def test_does_not_add_internal_credentials_by_default(self):
 
         assert "_litellm_internal_model_credentials" not in data
 
+    def test_routing_model_keeps_alias_over_credentials_model(self):
+        """
+        Two model groups can share one litellm_params.model; router-bound call
+        sites pass routing_model so the group alias survives the merge and the
+        router can still apply per-group access controls (#36103).
+        """
+        data = {"model": "team-a-gpt", "vector_store_id": "vs_1"}
+        credentials = {
+            "api_key": "sk-shared",
+            "custom_llm_provider": "openai",
+            "model": "openai/gpt-4o-mini",
+        }
+
+        prepare_data_with_credentials(
+            data=data, credentials=credentials, routing_model="team-a-gpt"
+        )
+
+        assert data["model"] == "team-a-gpt"
+        assert data["api_key"] == "sk-shared"
+        assert "custom_llm_provider" not in data
+
+    def test_credentials_model_lands_in_data_without_routing_model(self):
+        """Direct-to-SDK call sites still need the deployment model (#25104)."""
+        data = {"model": "bedrock-batch-alias"}
+        credentials = {
+            "aws_region_name": "us-west-2",
+            "model": "bedrock/us.anthropic.claude-haiku-4-5-20251001-v1:0",
+        }
+
+        prepare_data_with_credentials(data=data, credentials=credentials)
+
+        assert data["model"] == "bedrock/us.anthropic.claude-haiku-4-5-20251001-v1:0"
+        assert data["aws_region_name"] == "us-west-2"
+
 
 class TestRoundTrip:
     """Tests for encode -> decode round-trip integrity."""

tests/test_litellm/proxy/vector_store_endpoints/test_vector_store_endpoints.py

@@ -174,7 +174,8 @@ async def test_vector_store_file_list_resolves_credentials_from_model_query_para
 
     assert result["api_key"] == "sk-team-openai"
     assert result["api_base"] == "https://api.openai.com/v1"
-    assert result["model"] == "openai/gpt-4o-mini"
+    # routing stays on the model-group alias, not the deployment's provider model (#36103)
+    assert result["model"] == "team-openai"
     assert "custom_llm_provider" not in result
     llm_router.get_deployment_credentials_with_provider.assert_called_once_with(
         model_id="team-openai"
@@ -207,7 +208,8 @@ async def test_vector_store_file_list_resolves_single_openai_team_deployment():
 
     assert result["api_key"] == "sk-team-openai"
     assert result["api_base"] == "https://api.openai.com/v1"
-    assert result["model"] == "openai/gpt-4o-mini"
+    # routing stays on the model-group alias, not the deployment's provider model (#36103)
+    assert result["model"] == "team-openai"
     assert "custom_llm_provider" not in result
     llm_router.get_deployment_credentials_with_provider.assert_called_once_with(
         model_id="team-openai", team_id=None
@@ -245,7 +247,8 @@ async def test_vector_store_file_list_wildcard_model_hint_falls_back_to_team_dep
 
     assert result["api_key"] == "sk-team-openai"
     assert result["api_base"] == "https://api.openai.com/v1"
-    assert result["model"] == "openai/gpt-4o-mini"
+    # routing stays on the matched team alias, not the deployment's provider model (#36103)
+    assert result["model"] == "team-openai"
     assert "custom_llm_provider" not in result
     assert llm_router.get_deployment_credentials_with_provider.call_count == 3
 

tests/test_litellm/proxy/vector_store_endpoints/test_vector_store_tenant_guard.py

@@ -169,7 +169,9 @@ def get_credentials(model_id):
     assert response == {"ok": True}
     assert captured_data["vector_store_id"] == "vs_provider_native"
     assert captured_data["api_key"] == "sk-managed-deployment"
-    assert captured_data["model"] == "openai/managed-deployment"
+    # the alias survives the credential merge so router dispatch keeps the
+    # model-group identity (#36103)
+    assert captured_data["model"] == "managed-deployment"
     llm_router.get_deployment_credentials_with_provider.assert_called_once_with(
         model_id="managed-deployment"
     )