Discord

Read channels and history, send messages, react and open threads. Deliberately the same shape as Slack — both take their request path from the same shared transport.

npm i @forge/tools-discord

Tools

Tool	Effect	Approval	Notes
discord_list_channels	read	never	Text and announcement channels only — the ones these tools can post to
discord_read_messages	read	never	Bounded; reports truncated and the id to continue from
discord_get_message	read	never
discord_send_message	external-write	always	Mentions disabled — see below
discord_reply_message	external-write	always	Threaded to the message it answers
discord_add_reaction	internal-write	never	Carries no content and is reversible
discord_create_thread	external-write	always	From an existing message

Wire it up

import { createAgent } from "@forge/agentkit/providers";
import { createStaticCredentialResolver } from "@forge/agentkit/tools";
import { createDiscordToolkit } from "@forge/tools-discord";

const agent = createAgent({
  manifest: {
    id: "helper",
    name: "Helper",
    instructions: "Answer questions in the support channel. Open a thread for anything longer than a line.",
    modelPolicy: { role: "smart" },
  },
  tools: [
    createDiscordToolkit({
      credentialRef: "discord",
      // `Bot <token>` — the word is part of the value.
      resolver: createStaticCredentialResolver({
        discord: { scheme: "custom-header", header: "Authorization", value: `Bot ${process.env.DISCORD_BOT_TOKEN}` },
      }),
    }),
  ],
});

Credentials and scopes

A bot token from the Discord developer portal, sent as Authorization: Bot <token>. The word Bot is part of the value; omitting it fails with a bare 401 that says nothing useful. That is why this toolkit declares schemes: ["custom-header"] rather than bearer.

Then you must invite the bot, and this is the step people miss. Generate an invite URL with the bot scope and these permissions, then open it and pick a server:

To use	Permission
discord_list_channels	View Channels
discord_read_messages, discord_get_message	View Channels, Read Message History
discord_send_message, discord_reply_message	Send Messages
discord_add_reaction	Add Reactions, Read Message History
discord_create_thread	Create Public Threads, Send Messages in Threads

Permissions are per channel as well as per server: a bot with Send Messages at the server level can still be denied it in one channel by a channel override, and the failure is the same 50001 as never having been invited.

Message Content Intent. Reading message text from channels the bot was not mentioned in requires the privileged Message Content intent, enabled in the developer portal. Without it, content comes back empty and nothing says why — which reads exactly like an empty channel.

Behaviour worth knowing

An uninvited bot fails like a bad token, and this package tells them apart. Both are 401/403 shaped, and the remedies could not be more different — one is a click in a server's settings, the other is a new token. Discord's 50001, 50013, 10003 and 10004 mean the bot is not there or lacks a permission:

Discord refused this (code 50001). The token is being accepted, so this is not a credential problem:
the bot is either not a member of that server, or lacks a permission in that channel. Invite it with
the `bot` scope and grant View Channel, Read Message History and Send Messages where it should work.

A bare 401 says the opposite, in as many words. Conflating them is the single most common support question on this platform.

Sends cannot @everyone by accident. Discord's default honours every mention in a message's content, so an agent relaying a user's text is one character away from a mass ping. Every send goes out with allowed_mentions: { parse: [] }, and a reply does not ping the person it answers.

History pages by snowflake, not a cursor. A full page means there is probably more, so the result carries truncated and continueBeforeId rather than implying it saw everything.

Messages are counted in code points. String.length counts UTF-16 units, so 2000 emoji would be refused wrongly.

Message content is untrusted. It arrives fenced. A message instructing the model to post something is data, and the post would still stop for approval.

Limits

Not offered	Why
Deleting or editing messages	A deletion is irreversible and visible; editing someone's context after the fact is not an agent's call
Kick, ban, timeout, role changes	Moderator powers over people, where a wrong call cannot be walked back by another call
Voice channels and stage events	An entirely different protocol — a gateway connection, not a REST call
Slash commands and interactions	These are how a bot receives work, which is a deployment's HTTP endpoint rather than a tool
File and image upload	Multipart to a second host — the same deferral as Slack's upload_file
Embeds	The embed object has twenty fields and a nesting limit Discord enforces silently; worth its own design pass rather than a half version
Direct messages	A separate consent expectation from a public channel, and worth its own task
@everyone and role mentions	Deliberately unreachable, per the mention rule above. A mass ping should be a person's decision