How would one use `redactor add`?

Has anyone successfully used the redactor add functionality? I am getting an error: failed to create Job API client: BUILDKITE_AGENT_JOB_API_SOCKET empty or undefined

I tried passing --experiment=job-api, based on this but then got this error message:
The job-api experiment has been promoted to a stable feature in agent version v3.64.0. You can safely remove the –experiment job-api flag to silence this message and continue using the feature
(I’m pretty sure we’re using agent version 3.74.x)

Do I need to enable something else at agent startup in order to use the redactor?

Ok, got it working… need to make sure the environment has BUILDKITE_AGENT_JOB_API_SOCKET and BUILDKITE_AGENT_JOB_API_TOKEN available (they are available, but not displayed on the ENV tab… and I needed to explicitly make them available to the environment we use)