Address code review feedback: improve model detection, parameter filtering, and test coverage

- Refactor _is_ollama_model to use constants for better maintainability
- Make parameter filtering more explicit with clear comments
- Add type hints for better code clarity
- Add comprehensive edge case tests for model detection
- Improve test docstrings with detailed descriptions
- Move integration test to proper tests/ directory structure
- Fix lint error in test script by adding assertion
- All tests passing locally with improved code quality

Co-Authored-By: João <joao@crewai.com>

tests/agent_test.py

@@ -1691,7 +1691,17 @@ def test_agent_execute_task_with_ollama():
 
 @pytest.mark.vcr(filter_headers=["authorization"])
 def test_ollama_model_with_response_format():
-    """Test that Ollama models work correctly when response_format is provided."""
+    """
+    Test Ollama model compatibility with response_format parameter.
+    
+    Verifies:
+    - LLM initialization with response_format doesn't raise ValueError
+    - Agent creation with formatted LLM succeeds
+    - Successful execution without raising ValueError for unsupported response_format
+    
+    Note: This test may fail in CI due to Ollama server not being available,
+    but the core functionality (no ValueError on initialization) should work.
+    """
     from pydantic import BaseModel
     
     class TestOutput(BaseModel):
@@ -1719,7 +1729,14 @@ def test_ollama_model_with_response_format():
 
 @pytest.mark.vcr(filter_headers=["authorization"])
 def test_ollama_model_response_format_filtered_in_params():
-    """Test that response_format is filtered out for Ollama models in _prepare_completion_params."""
+    """
+    Test that response_format is filtered out for Ollama models in _prepare_completion_params.
+    
+    Verifies:
+    - Ollama model detection works correctly for various model formats
+    - response_format parameter is excluded from completion params for Ollama models
+    - Model detection returns correct boolean values for different model types
+    """
     from pydantic import BaseModel
     
     class TestOutput(BaseModel):
@@ -1739,7 +1756,14 @@ def test_ollama_model_response_format_filtered_in_params():
 
 
 def test_non_ollama_model_keeps_response_format():
-    """Test that non-Ollama models still include response_format in params."""
+    """
+    Test that non-Ollama models still include response_format in params.
+    
+    Verifies:
+    - Non-Ollama models are correctly identified as such
+    - response_format parameter is preserved for non-Ollama models
+    - Backward compatibility is maintained for existing LLM providers
+    """
     from pydantic import BaseModel
     
     class TestOutput(BaseModel):
@@ -1756,6 +1780,35 @@ def test_non_ollama_model_keeps_response_format():
     assert params.get("response_format") == TestOutput
 
 
+def test_ollama_model_detection_edge_cases():
+    """
+    Test edge cases for Ollama model detection.
+    
+    Verifies:
+    - Various Ollama model naming patterns are correctly identified
+    - Case-insensitive detection works properly
+    - Non-Ollama models containing 'ollama' in name are not misidentified
+    - Different provider prefixes are handled correctly
+    """
+    from crewai.llm import LLM
+    
+    test_cases = [
+        ("ollama/llama3.2:3b", True, "Standard ollama/ prefix"),
+        ("OLLAMA/MODEL:TAG", True, "Uppercase ollama/ prefix"),
+        ("ollama:custom-model", True, "ollama: prefix"),
+        ("custom/ollama-model", False, "Contains 'ollama' but not prefix"),
+        ("gpt-4", False, "Non-Ollama model"),
+        ("anthropic/claude-3", False, "Different provider"),
+        ("openai/gpt-4", False, "OpenAI model"),
+        ("ollama/gemma3:latest", True, "Ollama with version tag"),
+    ]
+    
+    for model_name, expected, description in test_cases:
+        llm = LLM(model=model_name)
+        result = llm._is_ollama_model(model_name)
+        assert result == expected, f"Failed for {description}: {model_name} -> {result} (expected {expected})"
+
+
 @pytest.mark.vcr(filter_headers=["authorization"])
 def test_agent_with_knowledge_sources():
     content = "Brandon's favorite color is red and he likes Mexican food."

tests/test_ollama_integration.py

@@ -0,0 +1,106 @@
+"""
+Integration tests for Ollama model handling.
+This module tests the Ollama-specific functionality including response_format handling.
+"""
+
+from pydantic import BaseModel
+from crewai.llm import LLM
+from crewai import Agent
+
+class GuideOutline(BaseModel):
+    title: str
+    sections: list[str]
+
+def test_original_issue():
+    """Test the original issue scenario from GitHub issue #3082."""
+    print("Testing original issue scenario...")
+    
+    try:
+        llm = LLM(model="ollama/gemma3:latest", response_format=GuideOutline)
+        print("✅ LLM creation with response_format succeeded")
+        
+        params = llm._prepare_completion_params("Test message")
+        if "response_format" not in params or params.get("response_format") is None:
+            print("✅ response_format correctly filtered out for Ollama model")
+        else:
+            print("❌ response_format was not filtered out")
+            
+        agent = Agent(
+            role="Guide Creator",
+            goal="Create comprehensive guides",
+            backstory="You are an expert at creating structured guides",
+            llm=llm
+        )
+        print("✅ Agent creation with Ollama LLM succeeded")
+        
+        assert agent.llm.model == "ollama/gemma3:latest"
+        
+    except ValueError as e:
+        if "does not support response_format" in str(e):
+            print(f"❌ Original issue still exists: {e}")
+            return False
+        else:
+            print(f"❌ Unexpected ValueError: {e}")
+            return False
+    except Exception as e:
+        print(f"❌ Unexpected error: {e}")
+        return False
+    
+    return True
+
+def test_non_ollama_models():
+    """Test that non-Ollama models still work with response_format."""
+    print("\nTesting non-Ollama models...")
+    
+    try:
+        llm = LLM(model="gpt-4", response_format=GuideOutline)
+        params = llm._prepare_completion_params("Test message")
+        
+        if params.get("response_format") == GuideOutline:
+            print("✅ Non-Ollama models still include response_format")
+            return True
+        else:
+            print("❌ Non-Ollama models missing response_format")
+            return False
+            
+    except Exception as e:
+        print(f"❌ Error with non-Ollama model: {e}")
+        return False
+
+def test_ollama_model_detection_edge_cases():
+    """Test edge cases for Ollama model detection."""
+    print("\nTesting Ollama model detection edge cases...")
+    
+    test_cases = [
+        ("ollama/llama3.2:3b", True, "Standard ollama/ prefix"),
+        ("OLLAMA/MODEL:TAG", True, "Uppercase ollama/ prefix"),
+        ("ollama:custom-model", True, "ollama: prefix"),
+        ("custom/ollama-model", False, "Contains 'ollama' but not prefix"),
+        ("gpt-4", False, "Non-Ollama model"),
+        ("anthropic/claude-3", False, "Different provider"),
+        ("openai/gpt-4", False, "OpenAI model"),
+    ]
+    
+    all_passed = True
+    for model, expected, description in test_cases:
+        llm = LLM(model=model)
+        result = llm._is_ollama_model(model)
+        if result == expected:
+            print(f"✅ {description}: {model} -> {result}")
+        else:
+            print(f"❌ {description}: {model} -> {result} (expected {expected})")
+            all_passed = False
+    
+    return all_passed
+
+if __name__ == "__main__":
+    print("Testing Ollama response_format fix...")
+    
+    success1 = test_original_issue()
+    success2 = test_non_ollama_models()
+    success3 = test_ollama_model_detection_edge_cases()
+    
+    if success1 and success2 and success3:
+        print("\n🎉 All tests passed! The fix is working correctly.")
+    else:
+        print("\n💥 Some tests failed. The fix needs more work.")