diff --git a/libs/community/langchain_community/chat_models/writer.py b/libs/community/langchain_community/chat_models/writer.py
index 4d76a6a5f4dea..6538bdd1491d1 100644
--- a/libs/community/langchain_community/chat_models/writer.py
+++ b/libs/community/langchain_community/chat_models/writer.py
@@ -110,7 +110,8 @@ def _default_params(self) -> Dict[str, Any]:
         }
 
     @model_validator(mode="before")
-    def validate_environment(self, values: Dict) -> Any:
+    @classmethod
+    def validate_environment(cls, values: Dict) -> Any:
         """Validates that api key is passed and creates Writer clients."""
         try:
             from writerai import AsyncClient, Client
@@ -120,10 +121,19 @@ def validate_environment(self, values: Dict) -> Any:
                 "Please install it with `pip install writerai`."
             ) from e
 
-        if not (values["client"] and values["async_client"]):
+        if not (values.get("client") and values.get("async_client")):
             api_key = get_from_dict_or_env(values, "api_key", "WRITER_API_KEY")
-            values["client"] = Client(api_key=api_key)
-            values["async_client"] = AsyncClient(api_key=api_key)
+            values.update({"client": Client(api_key=api_key)})
+            values.update({"async_client": AsyncClient(api_key=api_key)})
+
+        if not (
+            type(values.get("client")) is Client
+            and type(values.get("async_client")) is AsyncClient
+        ):
+            raise ValueError(
+                "'client' attribute must be with type 'Client' and "
+                "'async_client' must be with type 'AsyncClient' from 'writerai' package"
+            )
 
         return values
 
diff --git a/libs/community/tests/unit_tests/chat_models/test_writer.py b/libs/community/tests/unit_tests/chat_models/test_writer.py
index 8b20a10ef7adf..8a0c833794ca6 100644
--- a/libs/community/tests/unit_tests/chat_models/test_writer.py
+++ b/libs/community/tests/unit_tests/chat_models/test_writer.py
@@ -106,25 +106,31 @@ def __init__(
         self.choices = choices
 
 
-@pytest.mark.requires("writer-sdk")
+@pytest.mark.requires("writerai")
 class TestChatWriterCustom:
     """Test case for ChatWriter"""
 
+    from writerai import AsyncClient, Client
+
     def test_writer_model_param(self) -> None:
         """Test different ways to initialize the chat model."""
         test_cases: List[dict] = [
             {
                 "model_name": "palmyra-x-004",
+                "api_key": "key",
             },
             {
                 "model": "palmyra-x-004",
+                "api_key": "key",
             },
             {
                 "model_name": "palmyra-x-004",
+                "api_key": "key",
             },
             {
                 "model": "palmyra-x-004",
                 "temperature": 0.5,
+                "api_key": "key",
             },
         ]
 
@@ -280,10 +286,12 @@ def test_sync_completion(
         self, mock_unstreaming_completion: List[ChatCompletionChunk]
     ) -> None:
         """Test basic chat completion with mocked response."""
-        mock_client = MagicMock()
-        mock_client.chat.chat.return_value = mock_unstreaming_completion
+        mock_client = self.Client(api_key="key")
+        mock_client.chat.chat = MagicMock(return_value=mock_unstreaming_completion)
 
-        chat = ChatWriter(client=mock_client, async_client=AsyncMock())
+        async_client = self.AsyncClient(api_key="key")
+
+        chat = ChatWriter(client=mock_client, async_client=async_client)
 
         message = HumanMessage(content="Hi there!")
         response = chat.invoke([message])
@@ -416,7 +424,7 @@ class GetWeather(BaseModel):
         assert response.tool_calls[0]["args"]["location"] == "London"
 
 
-@pytest.mark.requires("writer-sdk")
+@pytest.mark.requires("writerai")
 class TestChatWriterStandart(ChatModelUnitTests):
     """Test case for ChatWriter that inherits from standard LangChain tests."""