diff --git a/libs/ai-endpoints/langchain_nvidia_ai_endpoints/_common.py b/libs/ai-endpoints/langchain_nvidia_ai_endpoints/_common.py
index 019cdb01..ce672690 100644
--- a/libs/ai-endpoints/langchain_nvidia_ai_endpoints/_common.py
+++ b/libs/ai-endpoints/langchain_nvidia_ai_endpoints/_common.py
@@ -74,8 +74,16 @@ class Config:
     api_key: Optional[SecretStr] = Field(description="API Key for service of choice")
 
     ## Generation arguments
-    timeout: float = Field(60, ge=0, description="Timeout for waiting on response (s)")
-    interval: float = Field(0.02, ge=0, description="Interval for pulling response")
+    timeout: float = Field(
+        60,
+        ge=0,
+        description="The minimum amount of time (in sec) to poll after a 202 response",
+    )
+    interval: float = Field(
+        0.02,
+        ge=0,
+        description="Interval (in sec) between polling attempts after a 202 response",
+    )
     last_inputs: Optional[dict] = Field(
         description="Last inputs sent over to the server"
     )
@@ -372,9 +380,7 @@ def _wait(self, response: Response, session: requests.Session) -> Response:
         start_time = time.time()
         # note: the local NIM does not return a 202 status code
         #       (per RL 22may2024 circa 24.05)
-        while (
-            response.status_code == 202
-        ):  # todo: there are no tests that reach this point
+        while response.status_code == 202:
             time.sleep(self.interval)
             if (time.time() - start_time) > self.timeout:
                 raise TimeoutError(
@@ -385,10 +391,12 @@ def _wait(self, response: Response, session: requests.Session) -> Response:
                 "NVCF-REQID" in response.headers
             ), "Received 202 response with no request id to follow"
             request_id = response.headers.get("NVCF-REQID")
-            # todo: this needs testing, missing auth header update
+            payload = {
+                "url": self.polling_url_tmpl.format(request_id=request_id),
+                "headers": self.headers_tmpl["call"],
+            }
             self.last_response = response = session.get(
-                self.polling_url_tmpl.format(request_id=request_id),
-                headers=self.headers_tmpl["call"],
+                **self.__add_authorization(payload)
             )
         self._try_raise(response)
         return response
diff --git a/libs/ai-endpoints/tests/unit_tests/test_202_polling.py b/libs/ai-endpoints/tests/unit_tests/test_202_polling.py
new file mode 100644
index 00000000..18469e63
--- /dev/null
+++ b/libs/ai-endpoints/tests/unit_tests/test_202_polling.py
@@ -0,0 +1,57 @@
+import requests_mock
+from langchain_core.messages import AIMessage
+
+from langchain_nvidia_ai_endpoints import ChatNVIDIA
+
+
+def test_polling_auth_header(
+    requests_mock: requests_mock.Mocker,
+    mock_model: str,
+) -> None:
+    infer_url = "https://integrate.api.nvidia.com/v1/chat/completions"
+    polling_url = "https://api.nvcf.nvidia.com/v2/nvcf/pexec/status/test-request-id"
+
+    requests_mock.post(
+        infer_url, status_code=202, headers={"NVCF-REQID": "test-request-id"}, json={}
+    )
+
+    requests_mock.get(
+        polling_url,
+        status_code=200,
+        json={
+            "id": "mock-id",
+            "created": 1234567890,
+            "object": "chat.completion",
+            "model": mock_model,
+            "choices": [
+                {
+                    "index": 0,
+                    "message": {"role": "assistant", "content": "WORKED"},
+                }
+            ],
+        },
+    )
+
+    client = ChatNVIDIA(model=mock_model, api_key="BOGUS")
+    response = client.invoke("IGNORED")
+
+    # expected behavior -
+    #  - first a GET request to /v1/models to check the model exists
+    #  - second a POST request to /v1/chat/completions
+    #  - third a GET request to /v2/nvcf/pexec/status/test-request-id
+    # we want to check on the second and third requests
+
+    assert len(requests_mock.request_history) == 3
+
+    infer_request = requests_mock.request_history[-2]
+    assert infer_request.method == "POST"
+    assert infer_request.url == infer_url
+    assert infer_request.headers["Authorization"] == "Bearer BOGUS"
+
+    poll_request = requests_mock.request_history[-1]
+    assert poll_request.method == "GET"
+    assert poll_request.url == polling_url
+    assert poll_request.headers["Authorization"] == "Bearer BOGUS"
+
+    assert isinstance(response, AIMessage)
+    assert response.content == "WORKED"