What documentation must a non-resident furnish to claim a treaty withholding rate?

s.159(8), Income-tax Act 2025 (old s.90(4)/(5)) makes treaty relief conditional — "only when" — on (a) a tax residency certificate obtained from the government of the residence country, and (b) the prescribed documents and information (the Form 10F lineage, mandatorily e-filed since 1 Oct 2022). The withholding mechanics confirm it: s.393(2) Note 2 applies the agreement rate where the treaty "applies to the payee" and the payee "has furnished a certificate referred to in section 159(8)". No TRC, no treaty rate — the s.207(2) 20% (plus surcharge and cess) applies.