Studio REST Report Call Fails 400 Validation on Pay Group Parameter
What it means
A Studio integration calling a custom report's REST URL can get a 400 Validation error on a Pay Group parameter even when the calling ISU has every plausible security domain enabled, because the failure is coming from the report's own prompt-level restriction on that field, not from integration security.
Troubleshooting
- Open the target report directly as an admin and try running it manually with the same Pay Group value the integration is passing, this isolates whether the problem is the parameter value itself versus integration security.
- Check the report's prompt definition for the Pay Group field for a validation restriction (a business process or field-level rule limiting which values are acceptable), not just Security tab access.
- Confirm the exact parameter value and format the integration sends (ID vs Reference ID vs WID) matches what the report prompt expects.
- If the restriction is intentional, adjust the report's prompt security or validation rule; if not, remove or loosen the restriction rather than continuing to add integration security domains, since domain security isn't the failure point here.
Test the report manually with the same Pay Group parameter value to confirm it's a report-level validation restriction, then adjust the report's prompt rule rather than integration security.
Document report-level prompt restrictions separately from integration security requirements when building Studio reports-as-a-service style calls, so future debugging doesn't waste time re-checking domain security for a validation rule that lives on the report itself.