Add cohere client

pyproject.toml

@@ -116,7 +116,7 @@ lint-fix = [
 ]
 
 [tool.hatch.envs.hatch-test]
-features = ["anthropic", "litellm", "llamaapi", "ollama", "openai", "otel"]
+features = ["anthropic", "litellm", "llamaapi", "ollama", "openai", "otel", "cohere"]
 extra-dependencies = [
     "moto>=5.1.0,<6.0.0",
     "pytest>=8.0.0,<9.0.0",

src/strands/models/__init__.py

@@ -3,7 +3,8 @@
 This package includes an abstract base Model class along with concrete implementations for specific providers.
 """
 
-from . import bedrock
+from . import bedrock, cohere
 from .bedrock import BedrockModel
+from .cohere import CohereModel
 
-__all__ = ["bedrock", "BedrockModel"]
+__all__ = ["bedrock", "BedrockModel", "cohere", "CohereModel"]

src/strands/models/cohere.py

@@ -0,0 +1,34 @@
+"""Cohere model provider using OpenAI compatibility API.
+
+- Docs: https://docs.cohere.com/docs/compatibility-api
+"""
+
+import logging
+
+from typing_extensions import Unpack
+
+from .openai import OpenAIModel
+
+logger = logging.getLogger(__name__)
+
+
+class CohereModel(OpenAIModel):
+    """Cohere model provider implementation using OpenAI compatibility API."""
+
+    class CohereConfig(OpenAIModel.OpenAIConfig):
+        """Configuration options for Cohere models."""
+
+        pass
+
+    def __init__(self, api_key: str, **model_config: Unpack[CohereConfig]):
+        """Initialize Cohere provider instance.
+
+        Args:
+            api_key: Cohere API key.
+            **model_config: Configuration options for the Cohere model.
+        """
+        client_args = {
+            "base_url": "https://api.cohere.com/compatibility/v1",
+            "api_key": api_key,
+        }
+        super().__init__(client_args=client_args, **model_config)

tests-integ/test_model_cohere.py

@@ -0,0 +1,43 @@
+import os
+
+import pytest
+
+import strands
+from strands import Agent
+from strands.models.cohere import CohereModel
+
+
+@pytest.fixture
+def model():
+    return CohereModel(
+        model_id="command-a-03-2025",
+        api_key=os.getenv("CO_API_KEY"),
+    )
+
+
+@pytest.fixture
+def tools():
+    @strands.tool
+    def tool_time() -> str:
+        return "12:00"
+
+    @strands.tool
+    def tool_weather() -> str:
+        return "sunny"
+
+    return [tool_time, tool_weather]
+
+
+@pytest.fixture
+def agent(model, tools):
+    return Agent(model=model, tools=tools)
+
+
+@pytest.mark.skipif(
+    "CO_API_KEY" not in os.environ,
+    reason="CO_API_KEY environment variable missing",
+)
+def test_agent(agent):
+    result = agent("What is the time and weather in New York?")
+    text = result.message["content"][0]["text"].lower()
+    assert all(string in text for string in ["12:00", "sunny"])

tests/strands/models/test_cohere.py

@@ -0,0 +1,143 @@
+import unittest.mock
+
+import pytest
+
+import strands
+from strands.models.cohere import CohereModel
+
+
+@pytest.fixture
+def cohere_client_cls():
+    with unittest.mock.patch.object(strands.models.openai, "openai") as mock_openai_mod:
+        yield mock_openai_mod.OpenAI
+
+
+@pytest.fixture
+def cohere_client(cohere_client_cls):
+    return cohere_client_cls.return_value
+
+
+@pytest.fixture
+def model_id():
+    return "m1"
+
+
+@pytest.fixture
+def model(cohere_client, model_id):
+    _ = cohere_client
+    return CohereModel(api_key="k1", model_id=model_id)
+
+
+@pytest.fixture
+def messages():
+    return [{"role": "user", "content": [{"text": "test"}]}]
+
+
+@pytest.fixture
+def system_prompt():
+    return "s1"
+
+
+def test__init__(cohere_client_cls, model_id):
+    model = CohereModel(api_key="k1", model_id=model_id, params={"max_tokens": 1})
+    tru_config = model.get_config()
+    exp_config = {"model_id": "m1", "params": {"max_tokens": 1}}
+    assert tru_config == exp_config
+    cohere_client_cls.assert_called_once_with(base_url="https://api.cohere.ai/compatibility/v1", api_key="k1")
+
+
+def test_update_config(model, model_id):
+    model.update_config(model_id=model_id)
+    tru_model_id = model.get_config().get("model_id")
+    exp_model_id = model_id
+    assert tru_model_id == exp_model_id
+
+
+def test_stream(cohere_client, model):
+    mock_tool_call_1_part_1 = unittest.mock.Mock(index=0)
+    mock_tool_call_2_part_1 = unittest.mock.Mock(index=1)
+    mock_delta_1 = unittest.mock.Mock(
+        content="I'll calculate", tool_calls=[mock_tool_call_1_part_1, mock_tool_call_2_part_1]
+    )
+    mock_tool_call_1_part_2 = unittest.mock.Mock(index=0)
+    mock_tool_call_2_part_2 = unittest.mock.Mock(index=1)
+    mock_delta_2 = unittest.mock.Mock(
+        content="that for you", tool_calls=[mock_tool_call_1_part_2, mock_tool_call_2_part_2]
+    )
+    mock_delta_3 = unittest.mock.Mock(content="", tool_calls=None)
+    mock_event_1 = unittest.mock.Mock(choices=[unittest.mock.Mock(finish_reason=None, delta=mock_delta_1)])
+    mock_event_2 = unittest.mock.Mock(choices=[unittest.mock.Mock(finish_reason=None, delta=mock_delta_2)])
+    mock_event_3 = unittest.mock.Mock(choices=[unittest.mock.Mock(finish_reason="tool_calls", delta=mock_delta_3)])
+    mock_event_4 = unittest.mock.Mock()
+    cohere_client.chat.completions.create.return_value = iter([mock_event_1, mock_event_2, mock_event_3, mock_event_4])
+    request = {"model": "m1", "messages": [{"role": "user", "content": [{"type": "text", "text": "calculate 2+2"}]}]}
+    response = model.stream(request)
+    tru_events = list(response)
+    exp_events = [
+        {"chunk_type": "message_start"},
+        {"chunk_type": "content_start", "data_type": "text"},
+        {"chunk_type": "content_delta", "data_type": "text", "data": "I'll calculate"},
+        {"chunk_type": "content_delta", "data_type": "text", "data": "that for you"},
+        {"chunk_type": "content_stop", "data_type": "text"},
+        {"chunk_type": "content_start", "data_type": "tool", "data": mock_tool_call_1_part_1},
+        {"chunk_type": "content_delta", "data_type": "tool", "data": mock_tool_call_1_part_1},
+        {"chunk_type": "content_delta", "data_type": "tool", "data": mock_tool_call_1_part_2},
+        {"chunk_type": "content_stop", "data_type": "tool"},
+        {"chunk_type": "content_start", "data_type": "tool", "data": mock_tool_call_2_part_1},
+        {"chunk_type": "content_delta", "data_type": "tool", "data": mock_tool_call_2_part_1},
+        {"chunk_type": "content_delta", "data_type": "tool", "data": mock_tool_call_2_part_2},
+        {"chunk_type": "content_stop", "data_type": "tool"},
+        {"chunk_type": "message_stop", "data": "tool_calls"},
+        {"chunk_type": "metadata", "data": mock_event_4.usage},
+    ]
+    assert tru_events == exp_events
+    cohere_client.chat.completions.create.assert_called_once_with(**request)
+
+
+def test_stream_empty(cohere_client, model):
+    mock_delta = unittest.mock.Mock(content=None, tool_calls=None)
+    mock_usage = unittest.mock.Mock(prompt_tokens=0, completion_tokens=0, total_tokens=0)
+    mock_event_1 = unittest.mock.Mock(choices=[unittest.mock.Mock(finish_reason=None, delta=mock_delta)])
+    mock_event_2 = unittest.mock.Mock(choices=[unittest.mock.Mock(finish_reason="stop", delta=mock_delta)])
+    mock_event_3 = unittest.mock.Mock()
+    mock_event_4 = unittest.mock.Mock(usage=mock_usage)
+    cohere_client.chat.completions.create.return_value = iter([mock_event_1, mock_event_2, mock_event_3, mock_event_4])
+    request = {"model": "m1", "messages": [{"role": "user", "content": []}]}
+    response = model.stream(request)
+    tru_events = list(response)
+    exp_events = [
+        {"chunk_type": "message_start"},
+        {"chunk_type": "content_start", "data_type": "text"},
+        {"chunk_type": "content_stop", "data_type": "text"},
+        {"chunk_type": "message_stop", "data": "stop"},
+        {"chunk_type": "metadata", "data": mock_usage},
+    ]
+    assert tru_events == exp_events
+    cohere_client.chat.completions.create.assert_called_once_with(**request)
+
+
+def test_stream_with_empty_choices(cohere_client, model):
+    mock_delta = unittest.mock.Mock(content="content", tool_calls=None)
+    mock_usage = unittest.mock.Mock(prompt_tokens=10, completion_tokens=20, total_tokens=30)
+    mock_event_1 = unittest.mock.Mock(spec=[])
+    mock_event_2 = unittest.mock.Mock(choices=[])
+    mock_event_3 = unittest.mock.Mock(choices=[unittest.mock.Mock(finish_reason=None, delta=mock_delta)])
+    mock_event_4 = unittest.mock.Mock(choices=[unittest.mock.Mock(finish_reason="stop", delta=mock_delta)])
+    mock_event_5 = unittest.mock.Mock(usage=mock_usage)
+    cohere_client.chat.completions.create.return_value = iter(
+        [mock_event_1, mock_event_2, mock_event_3, mock_event_4, mock_event_5]
+    )
+    request = {"model": "m1", "messages": [{"role": "user", "content": ["test"]}]}
+    response = model.stream(request)
+    tru_events = list(response)
+    exp_events = [
+        {"chunk_type": "message_start"},
+        {"chunk_type": "content_start", "data_type": "text"},
+        {"chunk_type": "content_delta", "data_type": "text", "data": "content"},
+        {"chunk_type": "content_delta", "data_type": "text", "data": "content"},
+        {"chunk_type": "content_stop", "data_type": "text"},
+        {"chunk_type": "message_stop", "data": "stop"},
+        {"chunk_type": "metadata", "data": mock_usage},
+    ]
+    assert tru_events == exp_events
+    cohere_client.chat.completions.create.assert_called_once_with(**request)