refactor(llm): framework-owned provider registry

Add register_provider/get_provider_names to LLMFramework protocol.
Public API (llm/providers/__init__.py) delegates to the active
framework instead of importing from LangChain internals directly.
LangChainFramework implements the new methods, routing to its
internal chat/llm provider registries. Backwards-compat aliases
register_chat_provider/register_llm_provider still work.

Author: Pouyanpi

nemoguardrails/integrations/langchain/llm_adapter.py

@@ -200,6 +200,29 @@ async def stream_async(
 
 
 class LangChainFramework:
+    def register_provider(self, name: str, provider_cls: Any) -> None:
+        from langchain_core.language_models import BaseChatModel
+
+        from nemoguardrails.integrations.langchain.providers.providers import (
+            register_chat_provider as _register_chat,
+        )
+        from nemoguardrails.integrations.langchain.providers.providers import (
+            register_llm_provider as _register_llm,
+        )
+
+        if isinstance(provider_cls, type) and issubclass(provider_cls, BaseChatModel):
+            _register_chat(name, provider_cls)
+        else:
+            _register_llm(name, provider_cls)
+
+    def get_provider_names(self) -> List[str]:
+        from nemoguardrails.integrations.langchain.providers.providers import (
+            get_chat_provider_names,
+            get_llm_provider_names,
+        )
+
+        return sorted(set(get_chat_provider_names() + get_llm_provider_names()))
+
     def create_model(
         self,
         model_name: str,

nemoguardrails/llm/providers/__init__.py

@@ -1,4 +1,4 @@
-# SPDX-FileCopyrightText: Copyright (c) 2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# SPDX-FileCopyrightText: Copyright (c) 2023-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
 # SPDX-License-Identifier: Apache-2.0
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -13,20 +13,44 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-# Re-export from new location for backwards compatibility.
-# Implementation moved to nemoguardrails/integrations/langchain/providers/.
-from nemoguardrails.integrations.langchain.providers import (
-    get_chat_provider_names,
-    get_community_chat_provider_names,
-    get_llm_provider_names,
-    register_chat_provider,
-    register_llm_provider,
-)
+from typing import Any, List
+
+from nemoguardrails.llm.frameworks import get_default_framework, get_framework
+
+
+def _active_framework():
+    return get_framework(get_default_framework())
+
+
+def register_provider(name: str, provider_cls: Any) -> None:
+    _active_framework().register_provider(name, provider_cls)
+
+
+def get_provider_names() -> List[str]:
+    return _active_framework().get_provider_names()
+
+
+def register_chat_provider(name: str, provider_cls: Any) -> None:
+    register_provider(name, provider_cls)
+
+
+def register_llm_provider(name: str, provider_cls: Any) -> None:
+    register_provider(name, provider_cls)
+
+
+def get_chat_provider_names() -> List[str]:
+    return get_provider_names()
+
+
+def get_llm_provider_names() -> List[str]:
+    return get_provider_names()
+
 
 __all__ = [
-    "get_chat_provider_names",
-    "get_community_chat_provider_names",
-    "get_llm_provider_names",
+    "register_provider",
+    "get_provider_names",
     "register_chat_provider",
     "register_llm_provider",
+    "get_chat_provider_names",
+    "get_llm_provider_names",
 ]

nemoguardrails/types.py

@@ -259,7 +259,8 @@ class LLMFramework(Protocol):
     """Protocol for pluggable LLM framework backends.
 
     Each framework (LangChain, LiteLLM, etc.) implements this protocol to
-    provide a factory for creating ``LLMModel`` instances.
+    provide a factory for creating ``LLMModel`` instances and managing
+    its own set of providers.
 
     ``model_kwargs`` carries all provider-specific configuration. Framework
     implementations extract what they need (e.g. LangChain pops ``mode``
@@ -272,3 +273,7 @@ def create_model(
         provider_name: str,
         model_kwargs: Optional[Dict[str, Any]] = None,
     ) -> LLMModel: ...
+
+    def register_provider(self, name: str, provider_cls: Any) -> None: ...
+
+    def get_provider_names(self) -> List[str]: ...

tests/test_types.py

@@ -455,9 +455,15 @@ def test_creation(self):
 class TestLLMFrameworkProtocol:
     def test_mock_satisfies_protocol(self):
         class MockFramework:
-            def create_model(self, model_name, provider_name, mode, model_kwargs):
+            def create_model(self, model_name, provider_name, model_kwargs=None):
                 return None
 
+            def register_provider(self, name, provider_cls):
+                pass
+
+            def get_provider_names(self):
+                return []
+
         assert isinstance(MockFramework(), LLMFramework)
 
     def test_incomplete_class_fails_protocol(self):