fix(websearch): route a hook's model on a JSON-configured provider and keep the request provider on an echoed model

litellm/litellm_core_utils/core_helpers.py

@@ -42,14 +42,19 @@ def names_a_provider(candidate: str) -> bool:
     """Whether a model name's leading segment is a provider rather than part of the model."""
     import litellm
     from litellm.litellm_core_utils.get_llm_provider_logic import is_registered_custom_provider
+    from litellm.llms.openai_like.json_loader import JSONProviderRegistry
 
     provider_names: Final = {getattr(provider, "value", provider) for provider in litellm.provider_list}
-    return candidate in provider_names or is_registered_custom_provider(candidate)
+    return (
+        candidate in provider_names
+        or JSONProviderRegistry.exists(candidate)
+        or is_registered_custom_provider(candidate)
+    )
 
 
 def qualify_agentic_followup_model(patch_model: str | None, model: str, custom_llm_provider: str) -> str:
     """Resolve the model an agentic follow-up re-dispatches, keeping a hook's own provider."""
-    if not patch_model:
+    if not patch_model or patch_model == model:
         return qualify_provider_stripped_model(model, custom_llm_provider)
     leading_segment: Final = patch_model.split("/", 1)[0]
     if leading_segment != patch_model and names_a_provider(leading_segment):

litellm/llms/custom_httpx/llm_http_handler.py

@@ -48,7 +48,10 @@ from litellm.litellm_core_utils.audio_utils.subtitle_utils import (
     SUBTITLE_RESPONSE_FORMATS,
     synthesize_subtitle_document,
 )
-from litellm.litellm_core_utils.core_helpers import set_provider_response_headers_in_hidden_params
+from litellm.litellm_core_utils.core_helpers import (
+    qualify_agentic_followup_model,
+    set_provider_response_headers_in_hidden_params,
+)
 from litellm.litellm_core_utils.get_litellm_params import AWS_CREDENTIAL_KWARGS_KEYS
 from litellm.litellm_core_utils.llm_request_utils import serialize_multipart_form_fields
 from litellm.litellm_core_utils.realtime_errors import (
@@ -5847,8 +5850,6 @@ class BaseLLMHTTPHandler:
         if patch.messages is None:
             raise ValueError("Agentic loop plan missing patched messages")
 
-        from litellm.litellm_core_utils.core_helpers import qualify_agentic_followup_model
-
         full_model_name: Final = qualify_agentic_followup_model(patch.model, model, custom_llm_provider)
 
         optional_params_for_followup: Final = dict(optional_params)

tests/unit/litellm_core_utils/test_core_helpers.py

@@ -662,6 +662,16 @@ def test_a_patched_sub_path_model_still_takes_the_request_provider():
     )
 
 
+def test_a_patched_model_on_a_json_configured_provider_reaches_that_provider():
+    assert qualify_agentic_followup_model("aihubmix/gpt-4o", "gpt-4o", "openai") == "aihubmix/gpt-4o"
+
+
+def test_a_patch_echoing_the_request_model_keeps_the_request_provider():
+    assert qualify_agentic_followup_model("openai/gpt-4o", "openai/gpt-4o", "openrouter") == (
+        "openrouter/openai/gpt-4o"
+    )
+
+
 def test_spend_metadata_merge_survives_the_logging_thread_inserting_into_the_request_metadata() -> None:
     metadata: Final[dict[str, object]] = {}
 

tests/unit/llms/custom_httpx/test_llm_http_handler.py

@@ -5368,3 +5368,9 @@ class TestAgenticFollowUpKeepsTheProviderPrefix:
 
         assert response.model == "claude-sonnet-4-5"
         assert response._hidden_params["custom_llm_provider"] == "anthropic"
+
+    @pytest.mark.asyncio
+    async def test_a_hook_echoing_an_org_style_model_stays_on_the_request_provider(self):
+        response = await self._run_followup("openai/gpt-4o", "openrouter", patched_model="openai/gpt-4o")
+
+        assert response._hidden_params["custom_llm_provider"] == "openrouter"