Wales kicking coach Neil Jenkins has agreed to become a member of staff at the Welsh Rugby Union.
The 40-year-old is Wales' record Test scorer with 1,049 points and is the latest coach to sign a new contract.
"Neil is a unique individual, with a unique set of skills," said WRU group chief executive Roger Lewis.
"He's one of the great points-scorers of all time, an amazing coach, an amazing mentor and you couldn't meet a nicer, more honest man."
Howley has signed a new contract with Wales until mid-2016, while Edwards and head coach Warren Gatland will also remain until at least the end of the 2015 World Cup.
Former Wales and Scarlets hooker McBryde is now contracted until the end of the 2011-12 season.
England assistant and forwards coach Graham Rowntree, who worked alongside Gatland, Edwards and Howley on the 2009 British and Irish Lions tour to South Africa, had been linked with a position in the Wales backroom staff.
But Gatland praised McBryde's contribution. "Robin has signed up to the end of the season and we'll make a decision on his future after that," he said.
"It is great Neil Jenkins, Rob Howley and Shaun Edwards have committed themselves to Wales and two of them are on full-time staff at the moment.
"But I want to give some credit to Robin McBryde and the great job he has done.
"As a young coach he has improved enormously in the last two or three seasons and I don't think you throw away that experience that he has developed over the last five or six years.
"I would hate to see that investment of time and effort and energy lost to Welsh rugby.
"I'm very conscious of making sure he won't be left out in the cold."
Lewis admitted the WRU had needed to fend off admirers of a backroom team that saw Wales to fourth place in the recent World Cup.
"There's always been offers for all of our coaches consistently over the past four years and Neil is a person who will be in huge demand," Lewis added.
"That's why I'm so pleased we've secured his services for the foreseeable future."
Wales face Australia at the Millennium Stadium on Saturday, 3 December in a replay of their World Cup bronze medal play-off.