Many tax credits are not refundable and an income tax return has to be filed in order to use them. As I'm not a specialist, I can't give you an answer with respect to refundable tax credits. However, I know that for non-refundable credits, invoices and income statements are required for eligibility. Forty-nine percent of retirees don't have access to them.
On February 12th, 2024. See this statement in context.