Slack

The Slack chatbot starts a workbench job when someone @mentions the bot in a channel. It connects through a Slack app in Socket Mode and replies in that channel. This is separate from the Slack tool, which the agent calls during a job.

Capabilities

The Slack chatbot connects via Socket Mode, an outbound websocket from Plural to Slack that streams channel messages and @mentions in real time. When someone @mentions the bot in a bound channel, Plural spawns a workbench job with the mention text as the prompt. The agent runs its investigation or task and replies in the same channel using Slack's chat API.

How it works:

• Receiving mentions — Slack delivers app_mention and message.* events to Plural over the Socket Mode websocket. The bot checks whether the message text contains its user ID (<@USER_ID>). If so, it creates a workbench job for the bound workbench with the message text as the prompt. If the mention is inside a thread and the parent message was also a bot mention, Plural queues the new mention as a follow-up prompt on the existing job rather than starting a new one.
• Replying — The spawned job automatically receives a Slack tool (the same connection used for the chatbot, backfilled on job start) so the agent can reply. The agent calls slack_post_message with the channel ID and, if replying in a thread, the original message's thread_ts. Agents can also call slack_react_to_message to add emoji reactions while the job is running.
• Threading — When a user @mentions the bot in a thread, Plural recognizes the parent message and either continues the same job (if the parent was a bot-triggered job) or starts a new job. Replies posted by the agent can use thread_ts to keep conversations grouped.

Authentication and scope requirements:

The setup guide details the two tokens needed for Socket Mode. Both are required; pasting the bot token into the app-level token field will not work.

• App-level token (xapp-) — Opens the Socket Mode websocket via apps.connections.open. Requires the connections:write scope.
• Bot user OAuth token (xoxb-) — Used for all Slack Web API calls after the websocket is open: reading channel history, posting messages, adding reactions, and resolving channel names. Requires bot token scopes including chat:write, channels:history, groups:history, reactions:read, and reactions:write.

The setup guide lists the full manifest and scope requirements for public channels, private channels, and direct messages.

Setup

Create the chatbot connection in the Console and follow the inline setup guide for app credentials and channel binding. That guide is maintained at js/console/public/setup-guides/chatbots/slack.md.

Related

• Chatbots