Sierra

Sierra sells an AI agent platform for customer experience, and on 10 December 2024 Elliot Greenwald published its founding text on outcome-based pricing: "you pay only when the software achieves specific, valuable outcomes." Escalations generally carry no charge. Greenwald's argument names a structural conflict inside legacy CX vendors: seat-based revenue shrinks as their own AI improves, while a vendor paid per resolved conversation has no such conflict.

In April 2026, Bret Taylor, co-founder and CEO, and engineers Vijay Iyengar, Arya Asemanfar and Angie Wang described rebuilding Sierra's engineering interview around coding agents including Claude Code. The old loop (two coding interviews, algorithms, system design, culture fit) captured mechanics. Its replacement is a three-part onsite: plan, two solo hours building with the tools of the candidate's choice, then review of product choices and code. Sierra swapped the coding phone screen for system design, on the reasoning that vibe coding is easy and scalable production is not, and hires for strengths rather than absence of weaknesses.

On 6 October 2026, Taylor and Clay Bavor announced Personal Agent Protocol, an open standard Meta and Sierra are developing with Genesys, Instinct, Rocket, Shopify, Stripe and Walmart. The consumer decides what access their agent gets, the business sets what that agent may do, sessions run on OAuth, and actions reach the business through its site, APIs built on standards like MCP and OpenAPI, or its own agent. Version 0.1 of the specification is promised before the end of the month.