Sierra, Meta Publish Personal Agent Protocol Backed by Walmart

Sierra and Meta on October 6 published a joint proposal called the Personal Agent Protocol, described by The Next Web as 'an open standard defining how personal AI agents authenticate with businesses and what those businesses let them do.' Walmart, Shopify, Stripe, Rocket, Genesys and Instinct are listed as founding partners, with a v0.1 specification due later in October.

The design is OAuth-based with tiered access. Agents can act as guests to 'check stock or a returns policy,' and once customers sign in they 'decide whether it gets read-only or write access,' with sessions that carry across channels so a pre-login question and a post-login order belong to one visit. 'The company chooses whether the agent works through its website, through its APIs using standards such as MCP and OpenAPI, or through an agent of its own,' reads the Sierra announcement post from Bret Taylor and Clay Bavor.

The pitch lands alongside a direct rival. Visa's Trusted Agent Protocol, launched in June, already lets agents 'buy from about 175 million merchants,' and 'Stripe and Shopify are now in both' camps. Payments, push notifications and more granular permissions are flagged as future extensions rather than v0.1 features.

It is the second agent-commerce standard to court the same acquirers inside four months, arriving in a stretch of 432 agent stories we have logged in 90 days and one day after our note on Meta scaling back staff use of Anthropic's Claude.