June 2025 Update

Slack has changed their Terms of Service, preventing users from indexing their data (source: Slack). As a result, the only way to add Slack information into Onyx is by using the search APIs that Slack provides. These APIs are significantly slower and lower quality than the previous index-based approach. Your data is your data — if you care about higher quality Slack search then please talk to your customer success representative and make it clear that this change reduces the value you get out of Slack. If you have any questions, please reach out to founders@onyx.app or send us a message in Slack.

Setting up

Authorization

1

Prerequisite

You must be an admin of the Slack workspace to set up the connector.
2

Open Slack apps

Navigate and sign in to https://api.slack.com/apps.
3

Create new app

Click the Create New App button in the top right. Select From an app manifest option. Select the relevant workspace from the dropdown and click Next.Slack app creation flow with manifest option selected
4

Paste manifest

Select the “YAML” tab, paste the following manifest into the text box, and click Next:
display_information:
  name: Onyx Search Assistant
  description: Search your Slack data as yourself
  background_color: "#4A154B"
oauth_config:
  redirect_urls:
    - <YOUR_ONYX_DOMAIN>/federated/oauth/callback
  scopes:
    user:
      - channels:read
      - groups:read
      - im:read
      - mpim:read
      - search:read
      - channels:history
      - groups:history
settings:
  org_deploy_enabled: false
  socket_mode_enabled: false
  token_rotation_enabled: false
For Onyx Cloud, the redirect_urls value should be https://cloud.onyx.app/federated/oauth/callback.
We do not currently support token rotation, so token_rotation_enabled: false is necessary.
1

Create app

Click the Create button.
2

Open Basic Information

In the app page, navigate to the Basic Information tab under the Settings header.
3

Copy client credentials

Copy the Client ID and Client Secret. Store those somewhere safe for the next step.
Slack Basic Information page with Client ID and Client Secret

Indexing

1

Open Slack connector

Navigate to the Connector Dashboard and select the Slack Connector.
2

Enter client credentials

Enter the Client ID and Client Secret from step 7. Click the Create button.Onyx Slack Federated connector settings showing client credentials
3

Complete OAuth

Head back to the main Chat page and go through the OAuth flow!
Every user will need to go through this OAuth flow. All DMs, public channels, and private channels that the user has access to will be searchable.
Slack OAuth consent screen for Onyx Search Assistant