new-prefix-command

name	new-prefix-command
description	Scaffold a new text (prefix) command in app/prefixes, e.g. ".ping". Use when asked to add a message-based or prefix command.

New prefix command

1. Read .agents/context.md (Prefix commands section) if not already loaded.
2. Create app/prefixes/<name>.ts.
3. Default-export a PascalCase class extending BasePrefixCommand, decorated with @Prefix, with a PrefixCommandBuilder on data.

import { User } from "discord.js";
import { Prefix, BasePrefixCommand, PrefixCommandBuilder, PrefixContext } from "engine";

@Prefix({ cooldown: 3 })
export default class Avatar extends BasePrefixCommand {
	data = new PrefixCommandBuilder().setName("avatar").setDescription("Shows a user's avatar.").addAlias("av").addUser("target", "The user to inspect");

	async execute(context: PrefixContext) {
		const target = context.args.target instanceof User ? context.args.target : context.message.author;
		await context.message.reply(target.displayAvatarURL({ size: 1024 }));
	}
}

Builder and context

• PrefixCommandBuilder deliberately mirrors SlashCommandBuilder naming (camelCase): setName, setDescription, addAlias, and typed addString / addInteger / addNumber / addBoolean / addUser / addMember / addChannel / addRole / addRest.
• context.args holds resolved typed arguments keyed by name; context.raw has string tokens and context.content the remainder. Also available: prefix, command, globals, permissions.
• @Prefix accepts cooldown and guilds like slash commands; aliases share the command's cooldown bucket.

Rules

• The subsystem is gated by config.prefix.enabled; the per-guild prefix lives in lib/prefixes.ts.
• Never hand-write a MessageCreate router; engine/prefix_dispatch.ts owns routing.
• No comments, snake_case locals and methods.

Verify

Run bun run typecheck and bun run lint. No deploy step is needed; prefix commands are live on next boot.