Providers

Decorate what the game already draws.

providers.nametag(function (p) { return fkdr.threat.tierOf(p.threat) === 'extreme' ? '§4✖ ' : ''; });
providers.tablist(function (p) { return p.tag ? ' §8[' + p.tag.label + ']' : ''; });
providers.clear();

Every script that offers one is asked, and the host concatenates the answers in load order, so two scripts can both contribute without fighting, which an event could not do.

Return a short coloured string or ''. Short means short: a nametag is drawn over somebody's head in a fight. You are called for every player, every frame, so cache anything expensive.

Registering again replaces your previous provider; the composition that matters is between scripts.

providers.nametagLive and providers.tablistLive say whether providers are working on your client, and /fkdr script hooks prints the same thing.