🇬🇧 EN

💬 Slack Message

Sends a message to a Slack channel or direct message using a Slack Incoming Webhook. No Slack app credentials are stored in Flusso — only the webhook URL you provide.

Category: Notifications & Messaging · Type identifier: slack_message

Overview

The Slack Message node posts a message to any Slack channel or user that your Slack Incoming Webhook is authorised for. Slack Incoming Webhooks are the simplest way to integrate Slack with external services — each webhook is tied to a specific channel and workspace in your Slack app settings.

Message text supports Slack's mrkdwn formatting, letting you include bold text, code blocks, and hyperlinks without configuring the full Slack API.

How to get a Slack Incoming Webhook URL

Create or open a Slack App Go to api.slack.com/apps and create a new app (or open an existing one) for your workspace.
Enable Incoming Webhooks In the app's left sidebar, click Incoming Webhooks and toggle the feature on.
Add a new webhook Click Add New Webhook to Workspace, choose the channel, and authorise. Slack gives you a URL beginning with https://hooks.slack.com/services/….
Copy the URL into Flusso Paste the webhook URL into the Webhook URL field of this node.

Configuration

Field	Required	Description
Webhook URL	Required	The Slack Incoming Webhook URL obtained from your Slack App configuration. Starts with `https://hooks.slack.com/services/`.
Message	Required	Message text to send. Supports Slack mrkdwn formatting and `{{ variable }}` references.
Channel Override	Optional	Override the default channel set in the Slack webhook. Use the channel name including the `#` prefix (e.g. `#alerts`). Leave blank to post to the webhook's default channel.
Username Override	Optional	Display name shown as the message sender (e.g. `Flusso Bot`). Overrides the app's default name.
Icon Emoji	Optional	Emoji code used as the bot's avatar, e.g. `:robot_face:`. Overrides the app's default icon.

Output Data

Field	Type	Description
`ok`	boolean	`true` if Slack accepted the message.
`ts`	string	The Slack message timestamp (unique message identifier within its channel).
`channel`	string	The channel the message was posted to.

Slack mrkdwn Quick Reference

Slack uses its own lightweight markup language. The most common tokens:

*bold text* → bold _italic text_ → italic `inline code` → monospace code ``` code block ``` → multi-line code block > blockquote text → indented blockquote <https://example.com|Link label> → hyperlink

Example Usage

Post an alert to #ops-alerts when a workflow run fails, including the error message from the trigger.

-- Webhook URL -- https://hooks.slack.com/services/T000/B000/xxxxxxxxxxxx -- Message -- :rotating_light: *Workflow failed*: {{ trigger.output.workflow_name }} Error: `{{ trigger.output.error_message }}` <https://app.flusso.io/runs/{{ trigger.output.run_id }}|View run details> -- Channel Override -- #ops-alerts

Tips & Notes

Store your Slack webhook URL securely. Anyone with the URL can post to your channel — do not share it publicly.
If you need to post to multiple channels, add multiple Slack Message nodes to your workflow, each with a different Webhook URL.
The ts output can be used in a follow-up Slack API call (via HTTP Request) to update or reply to the original message in a thread.
Channel Override only works if the Slack app has been authorised for that channel.

Related Nodes

Discord Message — equivalent node for Discord channels.
Telegram Message — send via Telegram Bot API.
Email Notification — email alternative for recipients outside Slack.
Webhook Notification — generic HTTP POST for other services.