On October 9, 2026, Sierra published a draft of the Personal Agent Protocol, known as Poppy, which describes how businesses can identify personal AI agents and set the ways they interact while customers approve account access. The proposal specifies a discovery file, permission controls and several possible business channels. Sierra’s announcement sets out the draft’s design. NeoTeo covered the initial announcement in an earlier report.

What the Poppy draft specifies

A business would publish a file at /.well-known/poppy.json describing how an agent can connect, how a session and sign-in work, and which interfaces the business offers. Sierra’s draft names OAuth, JSON Web Tokens (JWTs), HTTPS, OpenAPI and MCP among the standards it uses. The protocol site also describes access limited to approved scopes, which a user or the business can revoke.

The draft leaves businesses to choose which channels to offer: their website, APIs, their own conversational agent, or a combination. A session can begin as a guest; tasks that require an account involve signing in on the business’s own page through OAuth. The session can continue across the website, APIs and the business’s agent, so moving between those channels need not mean starting the interaction over.

That division gives each side a defined role: the business sets the available channels and access parameters, while the customer approves the access offered for the task. It is a proposal for coordinating those choices, not a description of one uniform setup across businesses.

What Sierra’s mortgage demonstration involved

Sierra described a demonstration in which Meta’s Muse agent found Rocket’s agent through Poppy and requested permission to connect. Rocket executive Alex McGillis signed in and shared credit and income details; the agents then worked through purchase price, down payment and interest rate. Sierra presented the example as a live demonstration, illustrating how the draft’s discovery and permission steps could fit into a mortgage interaction.

Sierra’s October 8 X post also described Muse working with Redfin and Rocket agents to find homes in Michigan and obtain mortgage preapproval. The post is Sierra’s account of the demonstration.

Who joined the design process

On October 9, Sierra named 35 additional design partners and said they would contribute to shaping the draft. The roster includes Adyen, Atomic, Bank of America, BBVA, Chime, Cigna, Cloudflare, Comcast, DIRECTV, ElevenLabs, FOX, Gap Inc., GEICO, Hertz, Insurify, Klaviyo, Liberty Mutual, Mastercard, Nordstrom, Notion, Okta, OneSignal, OpenAI, PayPal, Plaid, SiriusXM, Synchrony, Target, United Airlines, Venmo, Visa, Wells Fargo, Zapier, Zendesk and 1Password. Sierra’s announcement identifies their role as design partners.

The protocol site presents payments as a possible extension of Poppy, rather than a core capability specified in the draft. Personal Agent Protocol