This snippet will stop any non-admin in your server from posting messages larger than 450 letters/characters. Big thanks to aseboldt and NotEdwin for helping me!
const lib = require('lib')({token: process.env.STDLIB_SECRET_TOKEN});
let admins = ['role1', 'role2']
let memberAdminRoles = context.params.event.member.roles.filter( role => admins.includes(role))
if(memberAdminRoles) {
//you can change how many letters a message from a non-admin user can have.
//450 letters is around 5 lines in a discord message
if (context.params.event.content.length > 450) {
await lib.discord.channels['@0.1.0'].messages.create({
channel_id: `${context.params.event.channel_id}`,
content: `**[WARNING]** <@!${context.params.event.author.id}> please don't spam.`,
});
await lib.discord.channels['@0.1.1'].messages.destroy({
message_id: `${context.params.event.id}`,
channel_id: `${context.params.event.channel_id}`,
});
}
}