In the engine:packages/core/src/reviews.ts:98-106
function assertReviewerOrAdmin(user: User): void {
if (!canReview(user)) {
const err = new Error(
user.agent?.reviewOnly
? 'An agent can’t approve or reject reviews: a person does.'
: 'Only users with reviewer or admin role can perform this action'
);
(err as Error & { statusCode: number }).statusCode = 403;
throw err;A review-only agent fails the reviewer check, and the refusal says why in plain words.