GitHub Event payload forwarding?

All my searching around revealed no previous issues of this type.

I’m looking for the ability to access and tailor my pipelines’ behavior around the contents of the GitHub Event payload. I can’t find any way, in any Buildkite documentation nor in rooting through the pipeline settings, to actually observe the payload that fires it off. Any level of access would
suffice, even if just passing the blob as an envar to the agents.

I’m wondering if this is something that can be done, or if it’s planned anywhere? If it’s not, I’ll resubmit this as a feature request.