Add the Slack Message trigger
Create a workflow with a Slack Message trigger, use an existing workflow with a Slack Message trigger, or change an existing workflow’s trigger type to a Slack Message trigger.

Choose the message event type
Select either Message in Channel to run the workflow when a message is posted in a Slack channel, or Direct Message to trigger the workflow when a direct message is sent to Cassidy.
Select the channel
If you chose Message in Channel, select the Slack channel where you want the trigger to listen for messages.

Reference the trigger variables
In subsequent Workflow steps, you can reference the following variables from this trigger:
- Message Contents — the content of the message posted in Slack
- Message with History — full conversation history from the Slack channel, including previous messages and responses from Cassidy and other users
- Message with Thread History — thread-specific conversation history if the message is part of a thread
- Thread ID — the unique identifier for the thread if the message is part of a thread
- Channel ID — the unique identifier for the Slack channel where the message was posted
- Message ID — the unique identifier for the specific message
- Message Attachments — any files or attachments included with the message
- Sent By User — user information for the person who sent the message, including their Slack user ID, display name, and other profile details


