Using a variable to set Assignee in Jira Automation fails with 'Specify a valid value for assignee'

Question

Hi everyone,

I'm running into a puzzling issue with Jira Cloud automation. I want to set the assignee using a variable that contains the Atlassian account ID. If I hardcode the exact same account ID in my Advanced JSON—like this:

{ "fields": { "assignee": { "id": "5b10ac8d82e05b22cc7d4ef5" } } }

—it works perfectly, and the assignee is set without problems.

However, if I store that very same account ID in a variable (e.g., {{myUserId}}), and then reference it like:

{ "fields": { "assignee": { "id": "{{myUserId}}" } } }

--the rule fails with the error “Specify a valid value for assignee (assignee)”.

I’ve checked the following:

* The variable logs the correct account ID (confirmed via a Log Action).
* The user is active, has a Jira license, and has the “Assignable User” project permission.
* I’ve tried adding quotes, using asJsonString, etc.

Nothing seems to fix the error unless I manually hardcode the ID. Has anyone experienced this or know what might be causing the difference when using a variable versus a direct value?

Thanks in advance for any insights!

Kawa Akbulut · Answer

Hi @Bill Sheboy & @Kawan Diogo,

Thanks so much for your help!

I finally got it working!  Turns out the issue was that there was still a "Custodian" prefix before the actual ID in the variable, which Jira didn’t recognize as a valid user ID. Once I cleaned that up and ensured only the raw account ID was stored, the assignment worked perfectly.

Appreciate both of your insights and suggestions—they really helped me troubleshoot the issue!

Kind regards,
Kawa

Kawan Diogo_ykfovu · Answer

Hi @Kawa Akbulut

You can also use the Assign issue action in this automation, but perhaps you are using the advanced field edit, you can try something like you did with the asJsonString, the follow value:

{ "fields": { "assignee": { "id": "{{myUserId.trim}}" } } }

Best Regards.

Bill Sheboy · Answer

Hi @Kawa Akbulut -- Welcome to the Atlassian Community!

For a question like this, context is important for the community to help.  Please post the following:

* what type of project is this (e.g., company-managed, team-managed, etc.), 
* an image of your complete automation rule in a single image,
* images of any relevant actions / conditions / branches, and
* an image of the audit log details showing the rule execution

Until we see those...

Have you confirmed your variable does not contain any leading / trailing spaces?

Kind regards,
Bill