Agar has been at the club for four years (photo courtesy of Hull FC)
Hull FC have appointed Richard Agar as head coach following the departure of Peter Sharp last week.
The 36-year-old, who was Sharp's assistant at the KC Stadium, took charge of Hull's 16-8 defeat to St Helens in the Super League on Sunday.
Agar, who has signed a two-and-a-half year deal, told the club's website: "I am honoured to have been appointed head coach of this famous club.
"I am aware of the history of Hull FC and feel privileged to be part of it."
It will be Agar's second spell in charge of the club, although his first stint was a brief four-match stint as a caretaker boss in April 2006.
Agar, who played for Featherstone, Dewsbury and Widnes during his playing career, filled in for John Kear when the coach was not offered a new contract and steered the team to three wins before Sharp's arrival from Australia.
Former Widnes coach Neil Kelly said Agar's potential as a coach was clear.
"He was one of those players who you could see was always going to be a coach," Kelly told The Guardian.
"He was a very intelligent player who was a dream to coach because he was always willing to listen to ideas and offer some of his own. I'm sure he'll also be just as good to be coached by."
Hull FC chief executive James Rule added: "I believe Richard is a fantastic appointment for the club.
"He is highly respected by the players, staff and within the wider game of rugby league.
"His ambition and drive will be an integral part of the future development of Hull FC."
Agar is the son of former Featherstone coach Alan Agar, who led his side to a stunning win over Hull in the 1983 Challenge Cup final.