[Docs] Add ref in docstring about package location

libs/checkpoint-postgres/langgraph/store/postgres/aio.py

@@ -99,6 +99,13 @@ class AsyncPostgresStore(AsyncBatchedBaseStore, BasePostgresStore[_ainternal.Con
         2. Have the pgvector extension available to use vector search
         3. Use Python 3.10+ for async functionality
 
+    Tip:
+        This class is available in the [`langgraph-checkpoint-postgres` package](https://pypi.org/project/langgraph-checkpoint-postgres/).
+        Install with:
+        ```bash
+        pip install langgraph-checkpoint-postgres
+        ```
+
     Note:
         Semantic search is disabled by default. You can enable it by providing an `index` configuration
         when creating the store. Without this configuration, all `index` arguments passed to

libs/checkpoint-postgres/langgraph/store/postgres/base.py

@@ -578,6 +578,13 @@ class PostgresStore(BaseStore, BasePostgresStore[_pg_internal.Conn]):
         Semantic search is disabled by default. You can enable it by providing an `index` configuration
         when creating the store. Without this configuration, all `index` arguments passed to
         `put` or `aput`will have no effect.
+        
+    Tip:
+        This class is available in the [`langgraph-checkpoint-postgres` package](https://pypi.org/project/langgraph-checkpoint-postgres/).
+        Install with:
+        ```bash
+        pip install langgraph-checkpoint-postgres
+        ```
 
     Warning:
         Make sure to call `setup()` before first use to create necessary tables and indexes.

libs/checkpoint/langgraph/store/base/__init__.py

@@ -611,6 +611,11 @@ class BaseStore(ABC):
         by providing an `index` configuration at creation time. Without this
         configuration, semantic search is disabled and any `index` arguments
         to storage operations will have no effect.
+    
+    Note:
+        When deploying to the LangGraph Platform, your store (and checkpointer)
+        are managed by the platform. Do not manually create a store, as it will
+        be ignored.
     """
 
     __slots__ = ("__weakref__",)