diff --git a/tests/entrypoints/openai/responses/conftest.py b/tests/entrypoints/openai/responses/conftest.py
new file mode 100644
index 000000000..c9b524d40
--- /dev/null
+++ b/tests/entrypoints/openai/responses/conftest.py
@@ -0,0 +1,30 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+import pytest
+
+
+@pytest.fixture
+def pairs_of_event_types() -> dict[str, str]:
+    """Links the 'done' event type with the corresponding 'start' event type.
+
+    This mapping should link all done <-> start events; if tests mean to
+    restrict the allowed events, they should filter this fixture to avoid
+    copy + paste errors in the mappings or unexpected KeyErrors due to missing
+    events.
+    """
+    # fmt: off
+    event_pairs = {
+        "response.completed": "response.created",
+        "response.output_item.done": "response.output_item.added",
+        "response.content_part.done": "response.content_part.added",
+        "response.output_text.done": "response.output_text.delta",
+        "response.reasoning_text.done": "response.reasoning_text.delta",
+        "response.reasoning_part.done": "response.reasoning_part.added",
+        "response.mcp_call_arguments.done": "response.mcp_call_arguments.delta",
+        "response.mcp_call.completed": "response.mcp_call.in_progress",
+        "response.function_call_arguments.done": "response.function_call_arguments.delta", # noqa: E501
+        "response.code_interpreter_call_code.done": "response.code_interpreter_call_code.delta", # noqa: E501
+        "response.web_search_call.completed": "response.web_search_call.in_progress",
+    }
+    # fmt: on
+    return event_pairs
diff --git a/tests/entrypoints/openai/responses/test_harmony.py b/tests/entrypoints/openai/responses/test_harmony.py
index 2a942b9d8..ef014b2c2 100644
--- a/tests/entrypoints/openai/responses/test_harmony.py
+++ b/tests/entrypoints/openai/responses/test_harmony.py
@@ -280,24 +280,13 @@ async def test_stateful_multi_turn(client: OpenAI, model_name: str):
 
 @pytest.mark.asyncio
 @pytest.mark.parametrize("model_name", [MODEL_NAME])
-async def test_streaming_types(client: OpenAI, model_name: str):
+async def test_streaming_types(
+    pairs_of_event_types: dict[str, str], client: OpenAI, model_name: str
+):
     prompts = [
         "tell me a story about a cat in 20 words",
     ]
 
-    # this links the "done" type with the "start" type
-    # so every "done" type should have a corresponding "start" type
-    # and every open block should be closed by the end of the stream
-    pairs_of_event_types = {
-        "response.completed": "response.created",
-        "response.output_item.done": "response.output_item.added",
-        "response.content_part.done": "response.content_part.added",
-        "response.output_text.done": "response.output_text.delta",
-        "response.web_search_call.done": "response.web_search_call.added",
-        "response.reasoning_text.done": "response.reasoning_text.delta",
-        "response.reasoning_part.done": "response.reasoning_part.added",
-    }
-
     for prompt in prompts:
         response = await client.responses.create(
             model=model_name,
@@ -329,19 +318,9 @@ async def test_streaming_types(client: OpenAI, model_name: str):
 
 @pytest.mark.asyncio
 @pytest.mark.parametrize("model_name", [MODEL_NAME])
-async def test_function_calling_with_streaming_types(client: OpenAI, model_name: str):
-    # this links the "done" type with the "start" type
-    # so every "done" type should have a corresponding "start" type
-    # and every open block should be closed by the end of the stream
-    pairs_of_event_types = {
-        "response.completed": "response.created",
-        "response.output_item.done": "response.output_item.added",
-        "response.output_text.done": "response.output_text.delta",
-        "response.reasoning_text.done": "response.reasoning_text.delta",
-        "response.reasoning_part.done": "response.reasoning_part.added",
-        "response.function_call_arguments.done": "response.function_call_arguments.delta",  # noqa
-    }
-
+async def test_function_calling_with_streaming_types(
+    pairs_of_event_types: dict[str, str], client: OpenAI, model_name: str
+):
     tools = [GET_WEATHER_SCHEMA]
     input_list = [
         {
diff --git a/tests/entrypoints/openai/responses/test_mcp_tools.py b/tests/entrypoints/openai/responses/test_mcp_tools.py
index bca3fa171..13a40ecd8 100644
--- a/tests/entrypoints/openai/responses/test_mcp_tools.py
+++ b/tests/entrypoints/openai/responses/test_mcp_tools.py
@@ -210,19 +210,11 @@ class TestMCPEnabled:
     @pytest.mark.asyncio
     @pytest.mark.parametrize("model_name", [MODEL_NAME])
     async def test_mcp_tool_calling_streaming_types(
-        self, mcp_enabled_client: OpenAI, model_name: str
+        self,
+        pairs_of_event_types: dict[str, str],
+        mcp_enabled_client: OpenAI,
+        model_name: str,
     ):
-        pairs_of_event_types = {
-            "response.completed": "response.created",
-            "response.output_item.done": "response.output_item.added",
-            "response.content_part.done": "response.content_part.added",
-            "response.output_text.done": "response.output_text.delta",
-            "response.reasoning_text.done": "response.reasoning_text.delta",
-            "response.reasoning_part.done": "response.reasoning_part.added",
-            "response.mcp_call_arguments.done": ("response.mcp_call_arguments.delta"),
-            "response.mcp_call.completed": "response.mcp_call.in_progress",
-        }
-
         tools = [
             {
                 "type": "mcp",