fix(oci): report finish_reason="tool_calls" when the response carries tool calls

OCI non-streaming responses derived finish_reason solely from the provider's
raw stop reason via _normalize_oci_finish_reason. The OCI Cohere protocol has
no TOOL_CALLS finishReason — a tool-calling response comes back as "COMPLETE",
which normalizes to "stop" — so handle_cohere_response returned
finish_reason="stop" while message.tool_calls was populated, violating OpenAI
semantics (finish_reason must be "tool_calls" when the assistant message
contains tool calls). Override finish_reason to "tool_calls" whenever tool calls
are present, in both the Cohere and GENERIC response handlers.

litellm/llms/oci/chat/cohere.py

@@ -247,6 +247,13 @@ def handle_cohere_response(
             for i, tc in enumerate(cohere_response.chatResponse.toolCalls)
         ]
 
+    # Per OpenAI semantics a response carrying tool calls must report
+    # finish_reason="tool_calls". OCI's Cohere protocol has no TOOL_CALLS
+    # finishReason value (it returns "COMPLETE"), so _normalize_oci_finish_reason
+    # yields "stop"; override it when tool calls are present.
+    if tool_calls:
+        finish_reason = "tool_calls"
+
     content: Optional[str] = response_text if response_text else None
 
     # Only include ``tool_calls`` in the message dict when actually present.

litellm/llms/oci/chat/generic.py

@@ -377,6 +377,10 @@ def handle_generic_response(
     model_response.choices[0].finish_reason = _normalize_oci_finish_reason(  # type: ignore[union-attr,assignment]
         response_choice.finishReason
     )
+    # OpenAI semantics: a response carrying tool calls reports
+    # finish_reason="tool_calls" regardless of the provider's raw stop reason.
+    if message.tool_calls:
+        model_response.choices[0].finish_reason = "tool_calls"  # type: ignore[union-attr]
 
     oci_usage = completion_response.chatResponse.usage
     reasoning_tokens: Optional[int] = None

tests/test_litellm/llms/oci/chat/test_oci_finish_reason.py

@@ -0,0 +1,96 @@
+import datetime
+
+import httpx
+
+from litellm import ModelResponse
+from litellm.llms.oci.chat.transformation import OCIChatConfig
+
+
+def _transform(model: str, body: dict) -> ModelResponse:
+    response = httpx.Response(
+        status_code=200, json=body, headers={"Content-Type": "application/json"}
+    )
+    return OCIChatConfig().transform_response(
+        model=model,
+        raw_response=response,
+        model_response=ModelResponse(),
+        logging_obj={},  # type: ignore
+        request_data={},
+        messages=[],
+        optional_params={},
+        litellm_params={},
+        encoding={},
+    )
+
+
+def _cohere_body(with_tool_calls: bool) -> dict:
+    chat_response: dict = {
+        "apiFormat": "COHERE",
+        "text": "I will look up the weather in Tokyo.",
+        "finishReason": "COMPLETE",
+        "usage": {"promptTokens": 26, "completionTokens": 22, "totalTokens": 48},
+    }
+    if with_tool_calls:
+        chat_response["toolCalls"] = [
+            {"name": "get_weather", "parameters": {"location": "Tokyo"}}
+        ]
+    return {
+        "modelId": "cohere.command-latest",
+        "modelVersion": "1.0",
+        "chatResponse": chat_response,
+    }
+
+
+def _generic_body_with_tool_calls() -> dict:
+    created = (
+        datetime.datetime.now(datetime.timezone.utc).isoformat().replace("+00:00", "Z")
+    )
+    return {
+        "modelId": "meta.llama-3.3-70b-instruct",
+        "modelVersion": "1.0",
+        "chatResponse": {
+            "apiFormat": "GENERIC",
+            "choices": [
+                {
+                    "index": 0,
+                    "message": {
+                        "role": "ASSISTANT",
+                        "content": [{"type": "TEXT", "text": "Calling a tool."}],
+                        "toolCalls": [
+                            {
+                                "id": "call_0",
+                                "type": "FUNCTION",
+                                "name": "get_weather",
+                                "arguments": '{"location": "Tokyo"}',
+                            }
+                        ],
+                    },
+                    # OCI GENERIC may report STOP even when tool calls are present.
+                    "finishReason": "STOP",
+                }
+            ],
+            "timeCreated": created,
+            "usage": {"promptTokens": 5, "completionTokens": 10, "totalTokens": 15},
+        },
+    }
+
+
+def test_cohere_tool_calls_report_finish_reason_tool_calls():
+    # OCI Cohere returns finishReason="COMPLETE" for tool calls; finish_reason
+    # must still be "tool_calls" when the message carries them.
+    result = _transform("cohere.command-latest", _cohere_body(with_tool_calls=True))
+    assert result.choices[0].message.tool_calls is not None
+    assert result.choices[0].finish_reason == "tool_calls"
+
+
+def test_cohere_without_tool_calls_finish_reason_stop():
+    # Sanity: a plain COMPLETE response still maps to "stop".
+    result = _transform("cohere.command-latest", _cohere_body(with_tool_calls=False))
+    assert result.choices[0].message.tool_calls is None
+    assert result.choices[0].finish_reason == "stop"
+
+
+def test_generic_tool_calls_report_finish_reason_tool_calls():
+    result = _transform("meta.llama-3.3-70b-instruct", _generic_body_with_tool_calls())
+    assert result.choices[0].message.tool_calls is not None
+    assert result.choices[0].finish_reason == "tool_calls"