There is a hose attached to my the transmission dipstick. It has a green plastic cap the unscrews exposing a pressure valve similar to a valve stem.
What's it for?
Thank you, Bill
"...the man who really counts in the world is the doer, not the mere critic-the man who actually does the work, even if roughly and imperfectly, not the man who only talks or writes about how it ought to be done." T.R.(1891)
A valve like that under the hood is usually for servicing the air conditioning, but I would not expect it to be a hose, they usually teed off metal tubing.
Maybe you have supplemental air springs on the front, and the installer brought out connections so that you can check pressure and fill without crawling under the front end? In that case, you might look for another hose on the other side of the engine.