To delete your Grok chat history on grok.com/app or X, go to your chat settings...

https://garrettwigp625.tearosediner.net/how-do-i-delete-grok-imagine-images-and-generated-media

To delete your Grok chat history on grok.com/app or X, go to your chat settings and select delete conversation. Remember, this only removes text chats. Files and Imagine media stored in your account must be deleted separately