> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cassidyai.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Send Slack message

> Send a message to a Slack channel, thread, or DM as part of a Workflow.

The Send Slack Message action sends a message to a Slack channel as part of your [Workflow](/workflows/overview). Use it to post results, send notifications, or reply to the user or channel that triggered the workflow.

<Steps>
  <Step title="Add the Send Slack Message action">
    While editing a workflow, click the **+** button between existing blocks. This opens a modal where you can select from Cassidy's pre-configured actions. Choose **Send Slack Message** to add it to your workflow.

    <Frame>
      <img src="https://mintcdn.com/cassidy/g8fyfImJ_SyinsRX/images/reference/send-slack-message-img-0.png?fit=max&auto=format&n=g8fyfImJ_SyinsRX&q=85&s=cb2aff841dbbc73bb548534085306b0d" alt="Plus button between workflow blocks to add a new action" width="682" height="262" data-path="images/reference/send-slack-message-img-0.png" />
    </Frame>

    <Frame>
      <img src="https://mintcdn.com/cassidy/g8fyfImJ_SyinsRX/images/reference/send-slack-message-img-1.png?fit=max&auto=format&n=g8fyfImJ_SyinsRX&q=85&s=49315ed2c07bc716b1d4f0979ec18940" alt="Action picker modal with Send Slack Message selected" width="635" height="406" data-path="images/reference/send-slack-message-img-1.png" />
    </Frame>
  </Step>

  <Step title="Rename the action">
    If you want to make the action more descriptive or easier to reference as a variable later, enter a new name.

    <Frame>
      <img src="https://mintcdn.com/cassidy/g8fyfImJ_SyinsRX/images/reference/send-slack-message-img-2.png?fit=max&auto=format&n=g8fyfImJ_SyinsRX&q=85&s=b46e95e79cda86531ad7a30f3594a5b1" alt="Renaming the Send Slack Message action" width="633" height="129" data-path="images/reference/send-slack-message-img-2.png" />
    </Frame>
  </Step>

  <Step title="Connect your Slack account">
    If you haven't already, connect your Slack account to Cassidy.

    <Frame>
      <img src="https://mintcdn.com/cassidy/g8fyfImJ_SyinsRX/images/reference/send-slack-message-img-3.png?fit=max&auto=format&n=g8fyfImJ_SyinsRX&q=85&s=0d2ce2041c4e11521cba5df38f1fa350" alt="Slack connection prompt in the action configuration" width="635" height="890" data-path="images/reference/send-slack-message-img-3.png" />
    </Frame>
  </Step>

  <Step title="Toggle Reply to Trigger Message">
    Optionally, toggle on **Reply to Trigger Message** to reply to the same channel or user that sent the original message.

    <Frame>
      <img src="https://mintcdn.com/cassidy/g8fyfImJ_SyinsRX/images/reference/send-slack-message-img-4.png?fit=max&auto=format&n=g8fyfImJ_SyinsRX&q=85&s=42d30f7151cda4cc2aac26593a22d80f" alt="Reply to Trigger Message toggle enabled" width="634" height="110" data-path="images/reference/send-slack-message-img-4.png" />
    </Frame>
  </Step>

  <Step title="Select the channel">
    If **Reply to Trigger Message** is not toggled on, select the **Channel** to send the message to.

    <Frame>
      <img src="https://mintcdn.com/cassidy/g8fyfImJ_SyinsRX/images/reference/send-slack-message-img-5.png?fit=max&auto=format&n=g8fyfImJ_SyinsRX&q=85&s=9a32e4fbec63ec09c640498370ed551c" alt="Channel selector dropdown for the Send Slack Message action" width="634" height="158" data-path="images/reference/send-slack-message-img-5.png" />
    </Frame>

    <Tip>Private channels only appear after Cassidy has been added. In the desired channel, send `/invite @Cassidy`.</Tip>
  </Step>

  <Step title="Toggle Reply in a Thread">
    If **Reply to Trigger Message** is toggled on, you can also optionally toggle on **Reply in a Thread** to reply to the trigger message within its thread.

    <Frame>
      <img src="https://mintcdn.com/cassidy/g8fyfImJ_SyinsRX/images/reference/send-slack-message-img-6.png?fit=max&auto=format&n=g8fyfImJ_SyinsRX&q=85&s=ab472e8ca3b8046c52ccf9dafa00e003" alt="Reply in a Thread toggle enabled" width="632" height="95" data-path="images/reference/send-slack-message-img-6.png" />
    </Frame>
  </Step>

  <Step title="Enter the message">
    Enter the message to send to the channel. You can type the message directly or reference a variable containing the message from a previous step or the trigger.

    <Frame>
      <img src="https://mintcdn.com/cassidy/g8fyfImJ_SyinsRX/images/reference/send-slack-message-img-7.png?fit=max&auto=format&n=g8fyfImJ_SyinsRX&q=85&s=1a081596c298d7c714d85c1820b16999" alt="Message field with variable picker for inserting dynamic content" width="633" height="165" data-path="images/reference/send-slack-message-img-7.png" />
    </Frame>

    <Tip>Variables are inputs from the trigger, or outputs from previous steps. Use the variable picker to insert them.</Tip>
  </Step>
</Steps>

Here's a sample of the type of output you can expect:

<Frame>
  <img src="https://mintcdn.com/cassidy/g8fyfImJ_SyinsRX/images/reference/send-slack-message-img-8.png?fit=max&auto=format&n=g8fyfImJ_SyinsRX&q=85&s=04a94c655ee726d5a260bc449b2e6f68" alt="Sample Slack message output from the Send Slack Message action" width="533" height="845" data-path="images/reference/send-slack-message-img-8.png" />
</Frame>

## Fields

| Field                        | Description                                                                                      |
| ---------------------------- | ------------------------------------------------------------------------------------------------ |
| **Reply to Trigger Message** | When on, sends the message to the same channel or user that triggered the Workflow               |
| **Channel**                  | The Slack channel to send to (when not replying to trigger)                                      |
| **Reply in a Thread**        | When on, posts the message as a reply in the trigger message's thread                            |
| **Message**                  | The message content — supports plain text and [variables](/workflows/advanced/utility-variables) |

## Related

* [Slack Message trigger](/integrations/slack/slack-message-trigger)
* [Slack for Workflows](/integrations/slack/workflows)
* [Deploy an Agent to Slack](/integrations/slack/deploy-agent)