[Bugfix][Frontend] Support Responses text types in DeepSeek V4.1 (#56299)

Signed-off-by: CedricHuang <38417461+CedricHwong@users.noreply.github.com>
Co-authored-by: OpenAI Codex <codex@openai.com>

tests/tokenizers_/test_deepseek_v41.py

@@ -99,6 +99,24 @@ def test_raw_text_parts_preserve_reference_separator():
     assert messages == original
 
 
+@pytest.mark.parametrize(
+    ("role", "responses_type"),
+    [("user", "input_text"), ("assistant", "output_text")],
+)
+def test_responses_text_parts_match_chat_text_parts(role, responses_type):
+    responses_message = {
+        "role": role,
+        "content": [{"type": responses_type, "text": "hello"}],
+    }
+    chat_message = {
+        "role": role,
+        "content": [{"type": "text", "text": "hello"}],
+    }
+    assert render([responses_message], thinking=False) == render(
+        [chat_message], thinking=False
+    )
+
+
 def test_mid_system_gets_its_own_marker_and_generation_header():
     assert render(
         [

vllm/tokenizers/deepseek_v41.py

@@ -32,7 +32,7 @@ def _normalize_messages(
             parts = []
             for block in content:
                 part_type = block.get("type")
-                if part_type == "text":
+                if part_type in ("text", "input_text", "output_text"):
                     parts.append(block.get("text", ""))
                 elif part_type in ("image_url", "input_image", "image_pil"):
                     parts.append(IMAGE_PLACEHOLDER)