I have experienced that situation. My husband retired early at fifty from his local government job, with a pretty good pension, while I continued teaching for another fourteen years, until ill health forced me to retire.
The agreement was that he took over the running of the house, including cooking. The cooking part was soon dropped, when the children begged me to go back to doing the cooking! I agreed as his cooking was pretty awful and I was a fairly skilled cook.
At this time, I was also studying for another degree and admit to initially feeling somewhat resentful, when he was out golfing, while I was killing myself at the chalk face and spending weekends writing essays.
However, things settled down and it worked well. My husband quickly became bored, so took on some consultancy work in both the public and private sectors and studied part time at university as well. In the end we learned to compromise.
He found the mental stimulation, he was missing and the consultancy fees paid for luxuries, we otherwise wouldn't have been able to afford.
Its best to set the ground rules from the start. The stress of my husband's job, was taking a toll on his health and taking early retirement was a very wise move indeed.
Forward planning and communication is the key! I hope it works out for you both.