docs: Update pydantic compatibility (#25145)

Update pydantic compatibility

docs/docs/how_to/pydantic_compatibility.md

@@ -13,9 +13,14 @@ the v1 namespace of Pydantic 2.
 Because Pydantic does not support mixing .v1 and .v2 objects, users should be aware of a number of issues
 when using LangChain with Pydantic.
 
+:::caution
+While LangChain supports Pydantic V2 objects in some APIs (listed below), it's suggested that users keep using Pydantic V1 objects until LangChain 0.3 is released.
+:::
+
+
 ## 1. Passing Pydantic objects to LangChain APIs
 
-Most LangChain APIs that accept Pydantic objects have been updated to accept both Pydantic v1 and v2 objects.
+Most LangChain APIs for *tool usage* (see list below) have been updated to accept either Pydantic v1 or v2 objects.
 
 * Pydantic v1 objects correspond to subclasses of `pydantic.BaseModel` if `pydantic 1` is installed or subclasses of `pydantic.v1.BaseModel` if `pydantic 2` is installed.
 * Pydantic v2 objects correspond to subclasses of `pydantic.BaseModel` if `pydantic 2` is installed.