fix(llm): restore endpoint URL in LLMCallException via provider_url

The old _raise_llm_call_exception extracted endpoint URLs by checking
BASE_URL_ATTRIBUTES on the raw LangChain LLM. This was lost in the
rewrite. Restore it by using LLMModel.provider_url and implementing
the attribute inspection in LangChainLLMAdapter.provider_url.

Author: Pouyanpi

nemoguardrails/actions/llm/utils.py

@@ -277,12 +277,15 @@ def _raise_llm_call_exception(
     llm_call_info = llm_call_info_var.get()
     model_name = llm_call_info.llm_model_name if llm_call_info else model.model_name
     provider_name = llm_call_info.llm_provider_name if llm_call_info else model.provider_name
+    endpoint_url = model.provider_url
 
     context_parts = []
     if model_name:
         context_parts.append(f"model={model_name}")
     if provider_name:
         context_parts.append(f"provider={provider_name}")
+    if endpoint_url:
+        context_parts.append(f"endpoint={endpoint_url}")
 
     if context_parts:
         detail = f"Error invoking LLM ({', '.join(context_parts)})"

nemoguardrails/integrations/langchain/llm_adapter.py

@@ -130,8 +130,6 @@ def provider_name(self) -> Optional[str]:
 
     @property
     def provider_url(self) -> Optional[str]:
-        # temp: uses _BASE_URL_ATTRIBUTES which duplicates utils.py BASE_URL_ATTRIBUTES.
-        # utils.py copy will be removed in stack-3 when it switches to model.provider_url.
         for attr in _BASE_URL_ATTRIBUTES:
             value = getattr(self._llm, attr, None)
             if value: