diff --git a/integration-tests/conftest.py b/integration-tests/conftest.py
index 01250ce2..a2142af6 100644
--- a/integration-tests/conftest.py
+++ b/integration-tests/conftest.py
@@ -269,17 +269,25 @@ class ResponseComparator(JSONSnapshotExtension):
         def eq_chat_complete_chunk(
             response: ChatCompletionChunk, other: ChatCompletionChunk
         ) -> bool:
-            if response.choices[0].delta.content is not None:
-                return (
-                    response.choices[0].delta.content == other.choices[0].delta.content
-                )
-            elif response.choices[0].delta.tool_calls is not None:
-                return (
-                    response.choices[0].delta.tool_calls
-                    == other.choices[0].delta.tool_calls
-                )
+            if response.choices:
+                if response.choices[0].delta.content is not None:
+                    return (
+                        response.choices[0].delta.content
+                        == other.choices[0].delta.content
+                    )
+                elif response.choices[0].delta.tool_calls is not None:
+                    return (
+                        response.choices[0].delta.tool_calls
+                        == other.choices[0].delta.tool_calls
+                    )
+                else:
+                    raise RuntimeError(
+                        f"Invalid empty chat chunk {response} vs {other}"
+                    )
+            elif response.usage is not None:
+                return response.usage == other.usage
             else:
-                raise RuntimeError(f"Invalid empty chat chunk {response} vs {other}")
+                raise RuntimeError(f"Invalid empty chat {response} vs {other}")
 
         def eq_response(response: Response, other: Response) -> bool:
             return response.generated_text == other.generated_text and eq_details(
diff --git a/integration-tests/models/__snapshots__/test_tools_llama/test_flash_llama_grammar_tools_openai.json b/integration-tests/models/__snapshots__/test_tools_llama/test_flash_llama_grammar_tools_openai.json
index e6d78924..21023738 100644
--- a/integration-tests/models/__snapshots__/test_tools_llama/test_flash_llama_grammar_tools_openai.json
+++ b/integration-tests/models/__snapshots__/test_tools_llama/test_flash_llama_grammar_tools_openai.json
@@ -24,7 +24,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -57,7 +57,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -90,7 +90,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -123,7 +123,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -156,7 +156,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -189,7 +189,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -222,7 +222,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -255,7 +255,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -288,7 +288,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -321,7 +321,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -354,7 +354,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -387,7 +387,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -420,7 +420,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -453,7 +453,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -486,7 +486,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -519,7 +519,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -552,7 +552,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -585,7 +585,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -618,7 +618,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -651,7 +651,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -684,7 +684,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -717,7 +717,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -750,7 +750,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -783,7 +783,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195536,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -816,7 +816,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195537,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -849,7 +849,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195537,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -882,7 +882,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195537,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -915,7 +915,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195537,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -948,7 +948,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195537,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",
@@ -981,7 +981,7 @@
         "logprobs": null
       }
     ],
-    "created": 1741195537,
+    "created": 1741211702,
     "id": "",
     "model": "meta-llama/Llama-3.1-8B-Instruct",
     "object": "chat.completion.chunk",