This is a tutorial shows how to comment on an issue, this can be useful in many cases. For example to mention ceratin persons on creating or escalations.

Steps

Create a new Action by clicking CREATE button
Enter a name: Comment issue and click CREATE
Select Method: POST and URL: <your_base_url>/rest/api/2/issue/{{issue.key}}/comment
From the Atlassian REST API we can read to comment on an issue we need to call POST /rest/api/2/issue/{{issue.key}}/comment
Select Authentication method: Basic Auth, specify a user that has comment permission in the project
Add request headers, key: Content-Type with value application/json

On the Body section add the following

{
    "body":"RINT says hi {{issue.assignee.displayname}}!"
}

Click Triggers tab
Select ISSUE CREATED event
On JQL Condition. When to execute the event(s) write Project = TESTB and to limit the trigger to the TESTB project
Click SAVE
(Optional) Click Test button, Issue Key needs to be provided and click Send, Then go Log Tab.

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