core/config+agent: OpenAI provider_tools for hosted Responses tools

Merge opaque tool dicts (web_search, file_search, …) into POST /responses; local ToolRegistry unchanged.

tests/test_agent/test_responses_bridge.py

@@ -117,6 +117,23 @@ def test_chat_param_to_responses_kwargs() -> None:
     assert len(kwargs["tools"]) == 1
 
 
+def test_provider_tools_merged_after_local_functions() -> None:
+    param = ChatCompletionsParam(
+        model="gpt-test",
+        messages=[UserChatMessage(content="hi")],
+        tools=[ToolFunctionItem(function=ToolFunction(name="local_tool", parameters={"type": "object"}))],
+    )
+    kwargs = chat_param_to_responses_kwargs(
+        param,
+        provider_tools=[{"type": "web_search"}, {"type": "file_search", "vector_store_ids": ["vs_1"]}],
+    )
+    tools = kwargs["tools"]
+    assert len(tools) == 3
+    assert tools[0].name == "local_tool"
+    assert tools[1]["type"] == "web_search"
+    assert tools[2]["vector_store_ids"] == ["vs_1"]
+
+
 @pytest.mark.asyncio
 async def test_responses_chat_client_non_stream(monkeypatch: pytest.MonkeyPatch) -> None:
     from plyngent.lmproto.openai.client import OpenAIClient

tests/test_runtime/test_client_factory.py

@@ -24,6 +24,19 @@ def test_openai_provider_defaults_base_url() -> None:
     client = create_client(provider)
     assert isinstance(client, ResponsesChatClient)
     assert hasattr(client, "chat_completions")
+    assert client._provider_tools == []
+
+
+def test_openai_provider_tools_passed_to_wrapper() -> None:
+    from plyngent.agent.responses_client import ResponsesChatClient
+
+    provider = OpenAIProvider(
+        access_key_or_token="sk-test",
+        provider_tools=[{"type": "web_search"}],
+    )
+    client = create_client(provider)
+    assert isinstance(client, ResponsesChatClient)
+    assert client._provider_tools == [{"type": "web_search"}]
 
 
 def test_openai_compatible_requires_url() -> None: