Input tax credit: entitlement requires prescribed documentary compliance and furnishing of invoice details in GSTR-2. Claiming Input Tax Credit requires specified documents-supplier invoice, payment-linked invoice, supplier debit note, bill of entry for imports, or ISD documents-each containing all particulars prescribed in the Invoice Rules, with corresponding details furnished in FORM GSTR-2; credit is barred where tax was paid under an order confirming a demand arising from fraud, willful misstatement or suppression of facts.