Setting up a Slack Bot Connection with Unified.to

June 16, 2026

This guide walks you through connecting Slack Bot (slackbot) to Unified.to — including the Slack app settings you need for sending messages, interactive buttons, and receiving button-click events as Unified MessagingEvent webhooks.

Overview

A Slack Bot integration has three parts:

Important: two different URLs

Slack and your application use different webhook URLs. Do not point Slack at the same URL you use as your Unified hook_url.

Use your regional Unified API host and include your workspace ID, for example: https://api.unified.to/webhook/workspace/slackbot?workspace_id=YOUR_WORKSPACE_ID

EU and AU workspaces should use the corresponding regional API host (for example api-eu.unified.to or api-au.unified.to).

Step 1 — Create a Slack app

1. Go to https://api.slack.com/apps → Create New App → From scratch.
2. Name the app and select the Slack workspace you want to connect.
3. Click Create App.

Step 2 — Add OAuth scopes

Open OAuth & Permissions → Scopes → Bot Token Scopes and add the scopes for the objects you plan to use.

Minimum for sending messages, reading history, and receiving button clicks:

These mirror the messaging_message_write and messaging_event_read scope sets for the slackbot integration. Add additional scopes only if you use those objects.

Step 3 — Set the OAuth redirect URL

1. Under OAuth & Permissions → Redirect URLs, click Add New Redirect URL.
2. Paste the Unified OAuth callback URL shown in the dashboard when you connect Slack (bot). It looks like https://api.unified.to/oauth/code (use your region's host if applicable).
3. Save URLs.

Step 4 — Enable Interactivity

1. Go to Interactivity & Shortcuts and turn Interactivity ON.
2. Set Request URL to your Unified workspace webhook (not your hook_url): https://api.unified.to/webhook/workspace/slackbot?workspace_id=YOUR_WORKSPACE_ID
3. Save.

Unified receives Slack block_actions payloads here, converts button clicks into MessagingEvent objects with type BUTTON_CLICK, and forwards them to your hook_url.

Step 5 — (Optional) Enable Event Subscriptions

Enable this if you also want message, reaction, or channel membership events (not just button clicks).

1. Go to Event Subscriptions and turn it ON.
2. Set Request URL to the same Unified workspace webhook URL as Step 4: https://api.unified.to/webhook/workspace/slackbot?workspace_id=YOUR_WORKSPACE_ID
3. Under Subscribe to bot events, add the events you need, for example message.channels, app_mention, reaction_added, member_joined_channel.
4. Save.

Step 6 — Activate the integration, create a connection, and add a webhook

In the Unified dashboard (or via API), complete all three steps below.

1. Go to Integrations and activate Slack (bot) for your environment. If you use your own Slack app, enter your Client ID and Client Secret.
2. Create a connection for the Slack (bot) integration and complete the OAuth flow to install the app into your Slack workspace.
3. Create a webhook on that connection with object type messaging_event and event created. Set hook_url to your application endpoint (the URL where you want to receive Unified payloads).

Your hook_url is only configured on the Unified webhook subscription. Slack should always send events to the Unified workspace webhook from Steps 4–5.

Receiving events

When a user clicks a button or triggers a subscribed Slack event, Unified POSTs a normalized payload to your hook_url. Button clicks arrive as MessagingEvent objects with type BUTTON_CLICK — not as raw Slack block_actions JSON.

See the Unified webhook documentation for payload structure, signatures, and verification.

Troubleshooting