Access tokens for agents will now be limited to the lifetime of the job. There is now a unique BUILDKITE_AGENT_ACCESS_TOKEN for each job that is run, which will stop working once the job finishes. This reduces the period of impact to the lifetime of the job if a BUILDKITE_AGENT_ACCESS_TOKEN is leaked from the agent’s environment.
Ensure you are running Buildkite Agent version v3.39.0 or later to take advantage of these tokens and v3.62.0 for all the latest improvements.
For more details, see the documentation.