diff --git a/agent/agent_config.py b/agent/agent_config.py
index 751b922..bfb739a 100644
--- a/agent/agent_config.py
+++ b/agent/agent_config.py
@@ -81,11 +81,57 @@ class AgentConfig:
             'shell_env': self.shell_env,
         }
 
+    @staticmethod
+    def _redact_image_data(messages):
+        """Return a copy of messages with image base64/data URL payloads truncated.
+
+        Image content blocks can carry huge base64 strings; replace them with a short
+        placeholder so logs stay readable.
+        """
+        if not isinstance(messages, list):
+            return messages
+
+        def redact_value(value):
+            if isinstance(value, str) and value.startswith('data:'):
+                return value[:32] + '...[truncated]'
+            return value
+
+        redacted_messages = []
+        for message in messages:
+            if not isinstance(message, dict):
+                redacted_messages.append(message)
+                continue
+            content = message.get('content')
+            if not isinstance(content, list):
+                redacted_messages.append(message)
+                continue
+            redacted_content = []
+            for block in content:
+                if isinstance(block, dict) and block.get('type') in ('image', 'image_url'):
+                    new_block = block.copy()
+                    if 'base64' in new_block:
+                        new_block['base64'] = '[truncated]'
+                    if 'image_url' in new_block:
+                        image_url = new_block['image_url']
+                        if isinstance(image_url, dict):
+                            new_block['image_url'] = {**image_url, 'url': redact_value(image_url.get('url'))}
+                        else:
+                            new_block['image_url'] = redact_value(image_url)
+                    if 'url' in new_block:
+                        new_block['url'] = redact_value(new_block['url'])
+                    redacted_content.append(new_block)
+                else:
+                    redacted_content.append(block)
+            redacted_messages.append({**message, 'content': redacted_content})
+        return redacted_messages
+
     def safe_print(self):
         """Safely log the configuration without printing sensitive information."""
         safe_dict = self.to_dict().copy()
         if 'api_key' in safe_dict and isinstance(safe_dict['api_key'], str) and safe_dict['api_key'].startswith('sk-'):
             safe_dict['api_key'] = safe_dict['api_key'][:8] + '***' + safe_dict['api_key'][-6:]
+        if 'messages' in safe_dict:
+            safe_dict['messages'] = self._redact_image_data(safe_dict['messages'])
         logger.info(f"config={json.dumps(safe_dict, ensure_ascii=False)}")
 
     @classmethod