Drawing from thoughts of John MacDowell (“Mind and World”)
For a thought to be ‘about’ an object (world-directed, with empirical content) - it’s necessary that the correctness of the thought to be answerable to how things are.
For an intention to be an intention - it has to determine the correctness/incorrectness of some subsequent action.
A brain is not logically answerable to reality and is not overtly acting in the world, so it’s not fair to say it has thoughts or intentions.