The FIA has furnished teams with more information about how it intends to enforce its new clampdown on radio communications in Singapore and beyond.
Following feedback from fans, the governing body has banned any radio messages between the pitwall and the drivers that relate to "performance".
It is hoped that the clampdown will end the notion that today's complex cars are being driven in a sort of remote-control fashion by engineers and boffins.
Reports are now beginning to emerge about what precisely the FIA will allow and what may be subject to penalties this weekend as the ban falls under Singapore's lights.
Italy's Autosprint said information about the operation and function of energy-recovery is not allowed, as is notifications about tyre temperature, clutch settings and brake wear - among many other instructions outlined in a detailed document.
Additionally, any messages that appear encoded are not allowed.
It means that only basic radio messages are now permitted, including time gaps, positions, traffic and verbal encouragements such as "push".
Discussions about the selection of tyre compounds and wing adjustments, and the type of tyres used by competitors, are permitted, as are notifications of technical problems and race strategies.
Teams may also remind drivers to be aware of hazards, including the white line when rejoining from a pitstop and the limitations of the track.
And the ban will be in effect throughout not only the Grand Prix but also qualifying and practice sessions, Autosprint added.