Error "Missing GitHub OIDC request environment variables" is unhelpful

[ascott18]

If you try to set this action up by looking at the examples in the "Usage" part of the README, you then get a vague error "Missing GitHub OIDC request environment variables".

I'd love to see:

1. This error message improved, to provide suggested steps to remedy the problem (configure permissions for the workflow)
2. The README updated to include a full example at the top, rather than an almost-full example at the top that excludes a critical piece of configuration that's only included at the bottom of the file.

[thomaslevesque]

I just ran into the same error. I was missing the id-token: write permission, and I hope adding it will solve the issue... but on the other hand, if it does, it has nothing to do with what the error message says. So yeah, the message should definitely be improved.