Sierra partners with Stripe to enable AI agents to process payments during calls

Sierra, the artificial intelligence customer service startup led by Bret Taylor, has partnered with Stripe to allow its AI agents to process credit card payments during telephone conversations, according to a report by The Next Web. The partnership was announced on Tuesday, marking a shift in how AI-driven customer service handles financial transactions. Previously, customers often had to be transferred to another system or sent a separate payment link to complete a purchase or settle a bill.

With the new integration, the AI agent switches into a secure mode when a payment is required. The caller then types their card number directly onto their phone keypad. This data goes straight to Stripe for processing, ensuring that the AI agent itself never sees the full card details. Sierra stated that the agent only receives the payment status and the last four digits of the card number, a feature first added in April.

Operational Context and Standards

Sierra is now listed in the Stripe App Marketplace, allowing any business using Stripe to connect its AI agent without requiring custom development work, according to The Next Web. This integration aims to streamline the customer experience by keeping the interaction within a single call. The two firms are also collaborating on the Personal Agent Protocol, an open standard that Sierra and Meta announced this month.

The Personal Agent Protocol is designed to standardize how AI agents interact with businesses and handle transactions. Partners in this initiative include Instinct, a startup that raised $1 billion to build an agent that phones businesses on behalf of users. Sierra indicated that this open standard will also cover mechanisms for how agents can make payments on someone’s behalf, expanding the scope of agentic commerce beyond simple data retrieval.

Early Adoption and Market Impact

Healthcare billing firm Cedar was one of the first organizations to utilize this payment feature, according to The Next Web. Patients calling Cedar with questions about medical bills can now pay their balances during the same conversation. Dugan Winkie, Cedar’s chief strategy officer, noted that patients can arrive confused about a charge and leave with clarity and a resolved balance in one call.

Sierra reported that when patients start a payment with Cedar’s AI agent, 71.3% of those calls end in a successful payment. This high completion rate suggests that removing friction from the payment process can significantly improve outcomes for customer service interactions. Stripe has been heavily investing in payments by AI agents, with co-founder John Collison stating that agentic commerce will completely change online shopping.

What should you do?

Security and technology professionals should monitor how AI agents handle sensitive data in voice interactions. Organizations adopting AI customer service should verify that payment data is processed by certified third-party providers rather than stored by the AI model. Reviewing the Personal Agent Protocol standards may help in understanding future interoperability requirements for autonomous agents.

What to do and how to stay safe: Sierra

• Verify that AI customer service agents do not store or process full credit card numbers, ensuring data goes directly to payment processors.
• Monitor vendor updates regarding the Personal Agent Protocol to prepare for standardized agentic commerce interactions.
• Assess current call center workflows to identify opportunities where AI agents can streamline payment collection without compromising security.
• Review compliance requirements for AI-driven financial transactions to ensure adherence to data protection standards.

Step-by-step guide: Prompt Injection Warning Signs: How to Spot AI Manipulation

General security guidance from the Threat Times newsroom. It is not confirmed advice from the organisations named in this story.

Frequently asked questions

How do customers enter their payment information during an AI call?

Customers type their card number directly onto their phone keypad, and the data is sent straight to Stripe for processing.

Does the AI agent see the customer's full credit card number?

No, the AI agent never sees the card details, only the payment status and the last four digits of the card number.

What is the Personal Agent Protocol?

It is an open standard announced by Sierra and Meta that covers how agents interact with businesses and make payments on behalf of users.