diff --git a/datadog_lambda/durable.py b/datadog_lambda/durable.py
index e9443f92..3af4776f 100644
--- a/datadog_lambda/durable.py
+++ b/datadog_lambda/durable.py
@@ -43,7 +43,9 @@ def extract_durable_function_tags(event):
         return {}
 
     execution_name, execution_id = parsed
+    is_first_invocation = event.get("CheckpointToken") is None
     return {
         "durable_function_execution_name": execution_name,
         "durable_function_execution_id": execution_id,
+        "durable_function_first_invocation": str(is_first_invocation).lower(),
     }
diff --git a/tests/test_durable.py b/tests/test_durable.py
index 60914934..80770458 100644
--- a/tests/test_durable.py
+++ b/tests/test_durable.py
@@ -45,7 +45,7 @@ def test_works_with_numeric_version_qualifier(self):
 
 
 class TestExtractDurableFunctionTags(unittest.TestCase):
-    def test_extracts_tags_from_event_with_durable_execution_arn(self):
+    def test_extracts_tags_from_event_with_checkpoint_token(self):
         event = {
             "DurableExecutionArn": "arn:aws:lambda:us-east-1:123456789012:function:my-func:1/durable-execution/my-execution/550e8400-e29b-41d4-a716-446655440004",
             "CheckpointToken": "some-token",
@@ -57,6 +57,21 @@ def test_extracts_tags_from_event_with_durable_execution_arn(self):
             {
                 "durable_function_execution_name": "my-execution",
                 "durable_function_execution_id": "550e8400-e29b-41d4-a716-446655440004",
+                "durable_function_first_invocation": "false",
+            },
+        )
+
+    def test_extracts_tags_from_event_without_checkpoint_token(self):
+        event = {
+            "DurableExecutionArn": "arn:aws:lambda:us-east-1:123456789012:function:my-func:1/durable-execution/my-execution/550e8400-e29b-41d4-a716-446655440004",
+        }
+        result = extract_durable_function_tags(event)
+        self.assertEqual(
+            result,
+            {
+                "durable_function_execution_name": "my-execution",
+                "durable_function_execution_id": "550e8400-e29b-41d4-a716-446655440004",
+                "durable_function_first_invocation": "true",
             },
         )