On this page

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Available resources (Text format examples)

Get issue checklist

GET /rest/api/2/issue/{issueIdOrKey} (reference)

Returns the details of an issue, including its checklist.

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Create or update issue checklist

PUT /rest/api/2/issue/{issueIdOrKey} (reference)

Updates the issue including its checklist.

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• download current representation of the issue via GET /rest/api/2/issue/{issueIdOrKey}
• knowing Checklist Text field id, extract and parse checklist value: representation → fields → customfield_xxxxx (parse items by new line characters)
• modify parsed checklist according to your needs, for example to check item put "x" in its square brackets (so that "* [] summary" becomes "* [x] summary") 
• upload modified value back to the issue via PUT /rest/api/2/issue/{issueIdOrKey}

Add checklist to the issue (cURL)

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