User job permissions are the per-user, per-job access grants that pair a user with a Job Admin role on a specific job. Each row represents one (user_id, job_id, role_id) assignment; a user with access to multiple jobs appears in multiple rows. Site admins are not represented here — they have implicit access to every non-confidential job — so this endpoint only lists Job Admin grants. Filter with user_ids, job_ids, or role_ids to narrow the result set; combine with /v3/future_job_permissions (scope-based grants applied when matching jobs are later created) for the full picture of a user's job access.