user_id is now a required workflow_dispatch input (no default) and the runner validates it is non-empty before doing anything. Removed the 'jsahn' default from the script arg and replaced jsahn with <user_id> placeholders throughout TEST_WORKFLOW.md so the workflow is not pinned to one account. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>