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You can choose to assign checklist templates to your issues when the issue reaches a specific state. In order to that, click on the Switch to Filter link displayed after selecting Assign to projects tab.
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In addition to simple automation by issue type in a specific project, it is also possible to automate adding templates with the JQL filter, which makes the automation more flexible on when to add a checklist to the issue. Similarly, as with the simple automation, this action is reserved for project and Jira admins.
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To add automation via JQL filter click the Add automation button on the Manage template page and then select Automate with JQL Filter. Then you can either select an existing filter from the dropdown or if you don’t have any filters created yet, you can click
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Create filter to create one.
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As soon as an issue reaches a state that matches the JQL filter search, the chosen checklist template will be added to this issue. Each checklist template will be added only once.
A sample JQL filter that adds a checklist template when either a Story or a Task reaches the "Testing" status could look like below:
issuetype in (Story, Task) AND status = Testing
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JQL filters give you high flexibility on when to add checklists to issues.
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