Is an issue's timeSpent field editable?

[Gabriel]

It looks like I can't edit the timeSpent field in the issue object, neither via create issue or edit issue (https://docs.atlassian.com/software/jira/docs/api/REST/7.6.1/?_ga=2.80820181.351714748.1519344052-55782724.1518460860#api/2/issue-editIssue) endpoint. Is there some other endpoint to do this, or is it strictly the summation of timeSpent of associated worklogs?

[Jobin Kuruvilla [Adaptavist]]

It is the summation of associated worklogs. So, you will have to use the "Add worklog" API.

POST /rest/api/2/issue/{issueIdOrKey}/worklog