Hill, brought to the club by Dave Challinor who has since joined Stockport County, has wished Pools well for the future.
He was not in the bench for the FA Cup first round replay against Wycombe Wanderers on Tuesday night and his exit has now been confirmed.
Hill said: "’I’ve thoroughly enjoyed my short time at Hartlepool United working with a great set of lads and staff, and also getting to experience the famous atmosphere at the Vic.
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"I wish everybody connected to the club every success this season and for the future.’’
Sweeney added: “Clint has been nothing but brilliant since he came into the club.
"He obviously joined us at an unusual time following the sudden departure of Joe Parkinson but he’s been really good to me and the whole squad.
"He has been a great help since I took interim charge and we wish him all the best going forward.”