Post to Slack Channel
The Post to Slack Channel block sends a message to a Slack channel through a connected bot integration.
Send messages to a Slack channel via bot
The Post to Slack Channel block sends a message to a Slack channel through a connected bot integration. It accepts a channel ID and a message, and supports two message formats: a plain string message or a Slack Blocks message, where the message field contains a JSON string representing the blocks payload. If no channel ID or connection is specified in the block configuration, the user can select these at runtime.
What you can build
Real-world workflows powered by the Post to Slack Channel block.
AI Summary Notifications
Post an AI-generated summary of a document or report directly to a Slack channel after a summarization workflow completes.
Form Submission Alerts
Notify a Slack channel when a user submits a form in an AI app, passing the submitted data as a formatted message.
Error and Exception Logging
Send error messages or exception details to a designated Slack channel when a workflow encounters a failure condition.
Lead Capture Updates
Post new lead information collected by an AI assistant to a sales team Slack channel in real time.
Scheduled Report Delivery
Deliver periodic status reports or data digests to a Slack channel as part of a scheduled workflow.
Customer Support Escalation
Automatically post a support ticket summary to a Slack channel when an AI triage workflow flags a high-priority issue.
Ready to add Post to Slack Channel to your workflow?
Get Started FreeCommon questions about Post to Slack Channel
What are the required parameters for this block?
The block requires a channel ID (channelId) and a message (message), along with a messageType set to either 'string' for plain text or 'blocks' for a Slack Blocks JSON payload. A connectionId linking to a Slack bot integration is also needed, though both the connection and channel can be left unset to allow the user to select them at runtime.
What does the block return as output?
The block returns void, meaning it does not produce an output value that subsequent blocks can consume. It performs the action of posting the message and the workflow continues without a data output.
What is the difference between the 'string' and 'blocks' message types?
When messageType is set to 'string', the message field contains a plain text string. When set to 'blocks', the message field must contain a valid JSON string representing a Slack Blocks layout, which allows for richer message formatting using Slack's Block Kit structure.
What kinds of workflows commonly use this block?
This block is typically used at the end of a workflow to deliver a result or notification to a Slack channel — for example, after an AI generates a summary, processes a form submission, or flags an event that a team needs to act on.
Can the channel be selected dynamically rather than hardcoded?
Yes. If the channelId field is left as an empty string in the block configuration, the user will be prompted to select a channel at runtime. The same applies to the connectionId field.
Related capabilities
Fetch Slack Channel History
Fetch recent message history from a Slack channel.
Send Email
Send an email to one or more configured recipient addresses.
Send SMS
Send an SMS or MMS message to a phone number configured via OAuth connection.
Send Discord Follow-Up
Send a follow-up message to a Discord slash command interaction.
Send Discord Message
Send a message to Discord — either edit the loading message or send a new channel message.
Edit Discord Message
Edit a previously sent Discord channel message. Use with the message ID returned by Send Discord Message.
Add Post to Slack Channel to your workflow
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