Post to Slack
Publish text and files to a Slack channel.
Publish text messages and files to a public or private channel in the connected Slack workspace.
Slack limits
Characters4,000
ImagesUp to 10 · JPG/PNG/GIF/WebP
VideoMP4/WebM/MOV · up to 50 MB per file
PollsNot supported
Posts to a public or private channel in the connected Slack workspace.
Connect
Open Connect, click Connect on Slack, and authorize the DunSocial publish app. Each workspace connects one Slack team. This is a separate Slack app from the Slack agent in Settings → Integrations — connect Slack again here even if the agent is already installed.
What is supported
- Text messages (up to 4,000 characters).
- Up to 10 attachments (images and video). Per-file cap 50 MB.
- A channel picker in compose.
channelIdis required;channelNameis optional. - Scheduling and publishing right away.
Gotchas
- Choose a channel before you schedule. Posts without a channel will not publish.
- For a private channel, invite the DunSocial Slack app into that channel first.
- One Slack team per workspace. Reconnect Slack to switch teams.
- V1 is text and attachments only — no DMs, thread replies, Block Kit, or Slack analytics.
- If the publish app is uninstalled from Slack, reconnect Slack from the Connect screen.