The 52-year-old, who returned to Vale Park for a second spell in charge in 2011, is due to be out of contract this summer.
While there is still a chance that Adams could sign fresh terms with the club, he admits that a new deal is far from agreed.
"I am pleased with what I have achieved here but like footballers who come to the end of their contracts, managers too are free agents," he told Vale's official website.
"I am certainly not touting myself around but as far as the contract situation, this could have been sorted last summer.
"The future is bright for Port Vale, I am sure. Whether I am here or not is another matter, but I am certainly going to have a look at the contract.
"I am happy at the club, that's the thing, I am happy working with the people that I work with, but it is not only that - it is a big decision."
Port Vale are currently in 10th place in the League One table.