It was that page - OpenEVSE EV Charge Controller - Blog | OpenEnergyMonitor
But it was actually the 2nd link “A full list of RAPI Commands…” that I got the 404 error on.
The last link in the pasted bit below…
Regards
Rachel
"There is also an OpenEVSE RAPI command python library.
RAPI commands can be used to control and check the status of all OpenEVSE functions. A full list of RAPI commands can be found in the [OpenEVSE plus source code]****(https://github.com/OpenEVSE/open_evse/blob/stable/firmware/open_evse/src/rapi_proc.h)."