diff --git a/litellm/litellm_core_utils/streaming_handler.py b/litellm/litellm_core_utils/streaming_handler.py
index d2853a625c9..c24b67ac7ec 100644
--- a/litellm/litellm_core_utils/streaming_handler.py
+++ b/litellm/litellm_core_utils/streaming_handler.py
@@ -54,7 +54,8 @@ FUNCTION_CALL_ATTRIBUTE: Final = "function_call"
 
 _SYNC_ITER_EXHAUSTED: Final = object()
 
-_GCHUNK_FIELDS: Final[frozenset] = frozenset(GChunk.__annotations__)
+_GCHUNK_FIELDS: Final[frozenset[str]] = frozenset(GChunk.__annotations__)
+_GCHUNK_REQUIRED_FIELDS: Final[frozenset[str]] = frozenset(GChunk.__required_keys__)
 _USAGE_COST_HEADER_PROVIDERS: Final[frozenset[str]] = frozenset({LlmProviders.OPENROUTER.value})
 
 
@@ -2467,7 +2468,7 @@ def generic_chunk_has_all_required_fields(chunk: dict) -> bool:
     :param chunk: The dictionary to check.
     :return: True if all required fields are present, False otherwise.
     """
-    return all(key in _GCHUNK_FIELDS for key in chunk)
+    return _GCHUNK_REQUIRED_FIELDS <= chunk.keys() <= _GCHUNK_FIELDS
 
 
 def convert_generic_chunk_to_model_response_stream(
diff --git a/tests/unit/litellm_core_utils/test_streaming_overhead.py b/tests/unit/litellm_core_utils/test_streaming_overhead.py
index 8fb0659ab5a..f56c57f6c47 100644
--- a/tests/unit/litellm_core_utils/test_streaming_overhead.py
+++ b/tests/unit/litellm_core_utils/test_streaming_overhead.py
@@ -126,25 +126,17 @@ def test_gchunk_fields_is_frozenset():
     assert _GCHUNK_FIELDS == frozenset(GChunk.__annotations__)
 
 
-def test_generic_chunk_has_all_required_fields_uses_module_constant(monkeypatch):
-    """generic_chunk_has_all_required_fields must use _GCHUNK_FIELDS, not __annotations__.
-
-    The check semantics: every key in `chunk` must be a known GChunk field.
-    This identifies GChunk-shaped dicts (all keys are valid GChunk fields).
-    """
+def test_generic_chunk_has_all_required_fields_rejects_incomplete_chunks():
     valid_chunk = _make_generic_chunk("hello")
     assert generic_chunk_has_all_required_fields(valid_chunk) is True
 
-    # A dict with an extra unknown key should return False — the unknown key
-    # is not a GChunk field, so the chunk is not a pure GChunk.
     extra_key_chunk = dict(valid_chunk)
     extra_key_chunk["unknown_extra_key"] = "value"
     assert generic_chunk_has_all_required_fields(extra_key_chunk) is False
 
-    # A dict with only known GChunk fields but fewer keys still passes because
-    # all its keys are valid (subset of GChunk fields).
-    partial_chunk = {"text": "hi", "is_finished": False}
-    assert generic_chunk_has_all_required_fields(partial_chunk) is True
+    for required_field in GChunk.__required_keys__:
+        incomplete_chunk = {key: value for key, value in valid_chunk.items() if key != required_field}
+        assert generic_chunk_has_all_required_fields(incomplete_chunk) is False
 
 
 # ---------------------------------------------------------------------------