The 39-year-old former Ross County boss was chosen to take charge at Home Park after John Sheridan left at the end of last season, having lost in the League Two play-off semi-final.
Adams has been out of work since he was sacked by County in August, but has the full backing of Brent, with the chairman telling the club’s official website: “He gives a great confidence he knows what he’s doing.
“He knows how to get teams promoted and he knows how to motivate people. He’s obviously very tactically aware.”
He added: “(He is) very quiet, but very quietly confident and not arrogant in any way.
“He’s got some bright ideas and we look forward to supporting him in building a great team that hopefully play very attacking fast football and, most importantly, winning.”