fix: improve JSON console formatting for tool inputs

- Parse JSON strings in tool inputs for better readability
- Add proper error handling for malformed JSON
- Maintain existing string formatting as fallback
- Add comprehensive tests covering various input scenarios

Fixes #3474

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

tests/utilities/test_console_formatter_json.py

@@ -0,0 +1,174 @@
+import json
+from unittest.mock import patch
+
+from crewai.agents.parser import AgentAction, AgentFinish
+from crewai.events.utils.console_formatter import ConsoleFormatter
+
+
+class TestConsoleFormatterJSON:
+    """Test ConsoleFormatter JSON formatting functionality."""
+
+    def test_handle_agent_logs_execution_with_json_tool_input(self):
+        """Test that JSON tool inputs are properly formatted."""
+        formatter = ConsoleFormatter()
+
+        json_input = (
+            '{"task": "Research AI", "context": "Machine Learning", '
+            '"priority": "high"}'
+        )
+        agent_action = AgentAction(
+            thought="I need to research this topic",
+            tool="research_tool",
+            tool_input=json_input,
+            text="Full agent text",
+            result="Research completed"
+        )
+
+        with patch.object(formatter, 'print') as mock_print:
+            formatter.handle_agent_logs_execution(agent_action, "Test Agent")
+
+            assert mock_print.call_count == 4
+
+    def test_handle_agent_logs_execution_with_malformed_json(self):
+        """Test that malformed JSON falls back to string formatting."""
+        formatter = ConsoleFormatter()
+
+        malformed_json = (
+            '{"task": "Research AI", "context": "Machine Learning"'
+        )
+        agent_action = AgentAction(
+            thought="I need to research this topic",
+            tool="research_tool",
+            tool_input=malformed_json,
+            text="Full agent text",
+            result="Research completed"
+        )
+
+        with patch.object(formatter, 'print') as mock_print:
+            formatter.handle_agent_logs_execution(agent_action, "Test Agent")
+
+            assert mock_print.call_count == 4
+
+    def test_handle_agent_logs_execution_with_non_json_string(self):
+        """Test that non-JSON strings are handled properly."""
+        formatter = ConsoleFormatter()
+
+        plain_string = "search for weather in San Francisco"
+        agent_action = AgentAction(
+            thought="I need to search for weather",
+            tool="search_tool",
+            tool_input=plain_string,
+            text="Full agent text",
+            result="Weather found"
+        )
+
+        with patch.object(formatter, 'print') as mock_print:
+            formatter.handle_agent_logs_execution(agent_action, "Test Agent")
+
+            assert mock_print.call_count == 4
+
+    def test_handle_agent_logs_execution_with_complex_json(self):
+        """Test with complex nested JSON structures."""
+        formatter = ConsoleFormatter()
+
+        complex_json = json.dumps({
+            "query": {
+                "type": "research",
+                "parameters": {
+                    "topic": "AI in healthcare",
+                    "depth": "comprehensive",
+                    "sources": ["academic", "industry", "news"]
+                }
+            },
+            "filters": ["recent", "peer-reviewed"],
+            "limit": 50
+        })
+
+        agent_action = AgentAction(
+            thought="Complex research query",
+            tool="advanced_search",
+            tool_input=complex_json,
+            text="Full agent text",
+            result="Complex search completed"
+        )
+
+        with patch.object(formatter, 'print') as mock_print:
+            formatter.handle_agent_logs_execution(agent_action, "Test Agent")
+
+            assert mock_print.call_count == 4
+
+    def test_handle_agent_logs_execution_with_agent_finish(self):
+        """Test that AgentFinish objects are handled correctly."""
+        formatter = ConsoleFormatter()
+
+        agent_finish = AgentFinish(
+            thought="Task completed",
+            output="Final result of the task",
+            text="Full agent text"
+        )
+
+        with patch.object(formatter, 'print') as mock_print:
+            formatter.handle_agent_logs_execution(agent_finish, "Test Agent")
+
+            assert mock_print.call_count == 2
+
+    def test_json_parsing_preserves_structure(self):
+        """Test that JSON parsing preserves the original structure."""
+        formatter = ConsoleFormatter()
+
+        original_data = {
+            "nested": {
+                "array": [1, 2, 3],
+                "string": "test",
+                "boolean": True,
+                "null": None
+            }
+        }
+        json_string = json.dumps(original_data)
+
+        agent_action = AgentAction(
+            thought="Testing structure preservation",
+            tool="test_tool",
+            tool_input=json_string,
+            text="Full agent text",
+            result="Test completed"
+        )
+
+        with patch.object(formatter, 'print') as mock_print:
+            formatter.handle_agent_logs_execution(agent_action, "Test Agent")
+
+            assert mock_print.call_count == 4
+
+    def test_empty_tool_input_handling(self):
+        """Test handling of empty tool input."""
+        formatter = ConsoleFormatter()
+
+        agent_action = AgentAction(
+            thought="Empty input test",
+            tool="test_tool",
+            tool_input="",
+            text="Full agent text",
+            result="Test completed"
+        )
+
+        with patch.object(formatter, 'print') as mock_print:
+            formatter.handle_agent_logs_execution(agent_action, "Test Agent")
+
+            assert mock_print.call_count == 4
+
+    def test_numeric_tool_input_handling(self):
+        """Test handling of numeric tool input."""
+        formatter = ConsoleFormatter()
+
+        agent_action = AgentAction(
+            thought="Numeric input test",
+            tool="test_tool",
+            tool_input="42",
+            text="Full agent text",
+            result="Test completed"
+        )
+
+        with patch.object(formatter, 'print') as mock_print:
+            formatter.handle_agent_logs_execution(agent_action, "Test Agent")
+
+            assert mock_print.call_count == 4