On 13 Oct 2026 I posted on X about my deep‑dive into India’s Unified Payments Interface (UPI), tracing a single payment from end‑to‑end with senior leaders from PhonePe, Razorpay and NPCI.
UPI feels simple because most of what makes it work is invisible.
I followed one payment all the way through with Sameer Nigam (PhonePe), Harshil Mathur (Razorpay) and Sohini Rajola (NPCI): who moves the money, who pays the cost, and where fraud fits in.
- Money mover – the bank‑to‑bank settlement that actually transfers funds.
The conversation also opened a speculative scenario about autonomous AI agents that could shop and pay on a user’s behalf.
What would you let an AI agent buy without asking you first?
I did not record any formal decisions, but the open question flags a need to define consent boundaries before building AI‑driven payment products.
- Cost payer – the party that bears interchange and processing fees (often the aggregator or merchant).
- Fraud point – the layer where fraud detection is applied (aggregator, gateway, or NPCI).