Discord adapter

Setup

1. Create an application and bot in the Discord Developer Portal.
2. Under Bot → Privileged Gateway Intents, enable Message Content Intent. mikan requests this intent and cannot inspect ordinary message text without it.
3. Install the app with the bot and applications.commands scopes.
4. Grant the bot access required by the channels it will serve: View Channels, Send Messages, Read Message History, Add Reactions, Attach Files, Embed Links, and Send Messages in Threads.
5. Set the token and start mikan:

export DISCORD_BOT_TOKEN="..."
mikan /path/to/workspace

Channel permission overrides still apply. A successful installation does not guarantee access to every guild channel or private thread.

Event sources and triggers

The adapter handles:

• messageCreate in DMs, guild channels, and Discord thread channels
• slash commands: login, session, new, stop, model, and sandbox
• message attachments

DMs trigger directly. Guild messages normally require a mention, a reply/thread context that mikan handles, or a matching auto-reply policy. Stop commands are checked before the normal trigger gate.

Slash-command registration

The adapter does not keep its own command inventory. On connect it registers every src/commands/manifest.ts entry marked for Discord through application.commands.set(), taking the name, description, and optional string argument straight from the entry. Adding a command therefore means adding a manifest entry, not editing the adapter.

Discord rejects a registration whose command or option description exceeds 100 characters, and the whole set() call fails — which would silently leave the guild with a stale command list until the next restart. A unit test enforces the 100-character budget on every manifest description so that failure surfaces at test time instead.

Session rules

mikan uses resolveChatSessionKey() to isolate shared conversations. Discord passes persistentTopLevel: true, so a channel’s top-level conversation keeps one durable session instead of forking a new one per triggering message:

Scenario	Conversation id	Session key
DM	DM channel ID	the same DM channel ID
Guild top-level message	channel ID	the same channel ID
Discord thread channel	parent channel ID	<parentChannelId>:<threadChannelId>
Reply in a guild channel	channel ID	<channelId>:<referencedMessageId>
Slash command	same as above	resolved from the interaction’s context

So threads and replies fork their own session, while ordinary channel chatter continues the channel’s persistent one. A reply scopes to the message it directly references, not to a thread root that Discord does not provide for plain channel replies. DM replies are the exception: a DM is already a private conversation, so it stays on the bare channel key rather than forking per reply.

Replies and attachments

The responder supports Discord Markdown, typing indicators, initial replies, incremental message edits, reply targets, reactions, and file uploads. Long output is split below Discord’s message limit using a 1,900-character target.

Inbound attachments are downloaded into the conversation office’s attachments/ directory as <timestamp>_<sanitized-name> before the event reaches the runtime, through the same shared helper the other adapters use.

Guild slash-command acknowledgements are usually ephemeral; DM commands reply directly.

Current boundaries

mikan does not treat voice, embeds, components, polls, or every Discord media/event type as agent input. Thread/channel visibility is limited by the app installation and channel permissions.