Each plan includes a limited number of messages. A message is one interaction with the agent. Messages sent by the agent, tools used and other task accomplished programaticly doesn’t count toward your message quota. There is no token usage count on AppJet, all tokens are free and included with your plan. Messages automatically reset at each subscription renewal (including for free plan) and there is no roll over. Beside messages, there is no other cost associated with the usage of AppJet: deployments, builds and traffic are free and included in all plans.
On the free tier plan, it’s not possible to add a custom domain and deployments are deleted after 7 days.