LTI 1.3 Score POST Fails "User in requested score does not exist"

Sean.D.590 Posts: 1 🔍

I have a tool that integrates with D2L via LTI 1.3. While the LTI "Launch" flow works perfectly, I'm running into an issue when trying to post scores to the Line Item where the launch originated from. Assignments and Grade Services is enabled in the external tool settings (in D2L).

I've constructed the URL and request body following the IMS spec:

The user ID value used in the score POST request is the user_id included in the initial LTI Launch Claims (i.e. "" → "user_id"). I'm able to post scores to other LMS platforms using the same logic.

Any suggestions would be greatly appreciated!



  • Sean.D.501
    Sean.D.501 Posts: 1 🌱

    This was solved by using the value of the "sub" claim (of the LTI Launch Request claims) as the LTI User Id, rather than the "user_id" contained within the "" claims.