Fix AttributeError when agent_info is a list in YAML configuration

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

src/crewai/project/crew_base.py

@@ -123,6 +123,10 @@ def CrewBase(cls: T) -> T:
             cache_handler_functions: Dict[str, Callable],
             callbacks: Dict[str, Callable],
         ) -> None:
+            # If agent_info is a list, use the first item as the configuration
+            if isinstance(agent_info, list) and len(agent_info) > 0:
+                agent_info = agent_info[0]
+                
             if llm := agent_info.get("llm"):
                 try:
                     self.agents_config[agent_name]["llm"] = llms[llm]()

tests/project/test_yaml_config.py

@@ -0,0 +1,45 @@
+import pytest
+import yaml
+import tempfile
+from pathlib import Path
+import sys
+import os
+
+# Add a simple test to verify the fix works
+def test_list_format_in_yaml():
+    """Test that list format in YAML is handled correctly."""
+    # Create a test YAML content with list format
+    yaml_content = """
+    test_agent:
+      - name: test_agent
+        role: Test Agent
+        goal: Test Goal
+    """
+    
+    # Parse the YAML content
+    data = yaml.safe_load(yaml_content)
+    
+    # Get the agent_info which should be a list
+    agent_name = "test_agent"
+    agent_info = data[agent_name]
+    
+    # Verify it's a list
+    assert isinstance(agent_info, list)
+    
+    # Create a function that simulates the behavior of _map_agent_variables
+    # with our fix applied
+    def map_agent_variables(agent_name, agent_info):
+        # This is the fix we implemented
+        if isinstance(agent_info, list) and len(agent_info) > 0:
+            agent_info = agent_info[0]
+            
+        # Try to access a dictionary method on agent_info
+        # This would fail with AttributeError if agent_info is still a list
+        value = agent_info.get("name")
+        return value
+    
+    # Call the function - this would raise AttributeError before the fix
+    result = map_agent_variables(agent_name, agent_info)
+    
+    # Verify the result
+    assert result == "test_agent"