core[patch]: add standard tracing params for retrievers (#25240)

libs/core/langchain_core/retrievers.py

@@ -26,6 +26,8 @@ from abc import ABC, abstractmethod
 from inspect import signature
 from typing import TYPE_CHECKING, Any, Dict, List, Optional
 
+from typing_extensions import TypedDict
+
 from langchain_core._api import deprecated
 from langchain_core.documents import Document
 from langchain_core.load.dump import dumpd
@@ -50,6 +52,19 @@ RetrieverLike = Runnable[RetrieverInput, RetrieverOutput]
 RetrieverOutputLike = Runnable[Any, RetrieverOutput]
 
 
+class LangSmithRetrieverParams(TypedDict, total=False):
+    """LangSmith parameters for tracing."""
+
+    ls_retriever_name: str
+    """Retriever name."""
+    ls_vector_store_provider: Optional[str]
+    """Vector store provider."""
+    ls_embedding_provider: Optional[str]
+    """Embedding provider."""
+    ls_embedding_model: Optional[str]
+    """Embedding model."""
+
+
 class BaseRetriever(RunnableSerializable[RetrieverInput, RetrieverOutput], ABC):
     """Abstract base class for a Document retrieval system.
 
@@ -167,6 +182,19 @@ class BaseRetriever(RunnableSerializable[RetrieverInput, RetrieverOutput], ABC):
             len(set(parameters.keys()) - {"self", "query", "run_manager"}) > 0
         )
 
+    def _get_ls_params(self, **kwargs: Any) -> LangSmithRetrieverParams:
+        """Get standard params for tracing."""
+
+        default_retriever_name = self.get_name()
+        if default_retriever_name.startswith("Retriever"):
+            default_retriever_name = default_retriever_name[9:]
+        elif default_retriever_name.endswith("Retriever"):
+            default_retriever_name = default_retriever_name[:-9]
+        default_retriever_name = default_retriever_name.lower()
+
+        ls_params = LangSmithRetrieverParams(ls_retriever_name=default_retriever_name)
+        return ls_params
+
     def invoke(
         self, input: str, config: Optional[RunnableConfig] = None, **kwargs: Any
     ) -> List[Document]:
@@ -191,13 +219,17 @@ class BaseRetriever(RunnableSerializable[RetrieverInput, RetrieverOutput], ABC):
         from langchain_core.callbacks.manager import CallbackManager
 
         config = ensure_config(config)
+        inheritable_metadata = {
+            **(config.get("metadata") or {}),
+            **self._get_ls_params(**kwargs),
+        }
         callback_manager = CallbackManager.configure(
             config.get("callbacks"),
             None,
             verbose=kwargs.get("verbose", False),
             inheritable_tags=config.get("tags"),
             local_tags=self.tags,
-            inheritable_metadata=config.get("metadata"),
+            inheritable_metadata=inheritable_metadata,
             local_metadata=self.metadata,
         )
         run_manager = callback_manager.on_retriever_start(
@@ -250,13 +282,17 @@ class BaseRetriever(RunnableSerializable[RetrieverInput, RetrieverOutput], ABC):
         from langchain_core.callbacks.manager import AsyncCallbackManager
 
         config = ensure_config(config)
+        inheritable_metadata = {
+            **(config.get("metadata") or {}),
+            **self._get_ls_params(**kwargs),
+        }
         callback_manager = AsyncCallbackManager.configure(
             config.get("callbacks"),
             None,
             verbose=kwargs.get("verbose", False),
             inheritable_tags=config.get("tags"),
             local_tags=self.tags,
-            inheritable_metadata=config.get("metadata"),
+            inheritable_metadata=inheritable_metadata,
             local_metadata=self.metadata,
         )
         run_manager = await callback_manager.on_retriever_start(