Limits & Errors
Analytics availability, what Slack's API does not expose and the common errors when publishing.
Analytics
Slack has no public message analytics API, so GET /v1/analytics?platform=slack reports zero for every Slack post. Reactions and thread replies reach you through the inbox instead.
What you cannot do
Slack's bot API does not expose:
- Messaging people outside the connected workspace
- Posting to several channels from one connected account (connect each channel separately)
- Choosing the channel per post (
channelIdinplatformSpecificDatareturns a400) - Engagement metrics
- Message history from before the connection
- Joining a private channel without being invited
Common errors
| Error | Cause | Fix |
|---|---|---|
| Bot is not a member of this channel | The bot was removed, or the channel is private | Run /invite @Zernio in the channel. |
| Channel was not found or the bot lost access | The channel was deleted or the bot lost visibility | Reconnect, or connect another channel. |
| A workspace setting prevents posting | A Slack admin restricted posting in that channel | Only a Slack admin can lift it. |
| File uploads are disabled or too large | The workspace's upload policy or its free-plan storage cap | Check the workspace's upload policy and storage. |
| Workspace access was revoked | The app was uninstalled from Slack | Reconnect from the dashboard. |
missing_scope on inbound messages | The workspace was connected before the inbox shipped | Reconnect once. |
A publishNow: true post that Slack rejects returns 207 with post.status: "failed" and the message in platforms[].errorMessage:
{
"message": "Post created but publishing failed",
"error": "All platforms failed",
"post": {
"_id": "65f1c0a9e2b5af0012ab34cd",
"status": "failed",
"platforms": [
{
"platform": "slack",
"status": "failed",
"errorMessage": "Bot is not a member of this channel"
}
]
}
}207 is a 2xx status, so fetch(...).ok is true; branch on the status code and on post.status. Error handling covers the envelope.
Disconnecting one channel account does not revoke the workspace token, so sibling channel accounts keep working. Uninstalling the Zernio app from Slack disconnects every channel account of that workspace in Zernio automatically.