Sierra released version 1.0 of Personal Agent Protocol, or Poppy, on Friday, in a post by Bret Taylor and Clay Bavor. Shopify has enabled it for every merchant on its platform, and it is on for everyone who uses Muse, Meta’s AI agent, which the post says “automatically looks for Poppy first on every site it visits”.
Sierra says 60 new companies are joining as design partners, bringing the total to more than 100. That is up from the eight initial partners it names and 43 after the draft on 9 October, by our arithmetic, in 38 days. We covered the launch with Meta on 6 October.
Business Pill · The Model and the Harness
An evergreen Business Engineer explainer on why products built on the same model differ: the harness around it. It teaches the general idea only and does not discuss Sierra or Poppy.
The key insight: As we read the release, Poppy’s reach on day one comes from distribution it did not have to build: Shopify publishes a Poppy file for every store, and Meta’s Muse looks for Poppy first on every site it visits.
Poppy, the post says, “enables personal agents to interact with companies through business agents, websites, and APIs”. It is largely built with existing standards such as MCP, OpenAPI and UCP, and uses OAuth so that customers control what personal agents can and can’t do.
Since the draft, Sierra says, it has made the protocol easier to adopt in stages, refined how it uses existing standards, expanded a company’s ability to give guidance to and collect feedback from the personal agent, and introduced extensions, such as a commerce extension co-authored by Shopify. Any company can now implement it on its own, with an implementation kit that includes a validator.
Personal Agent Protocol design partners: eight initial partners Sierra names, 43 after 35 joined with the 9 October draft and 103 after 60 joined with version 1.0 on 13 November. 43 and 103 are our arithmetic; Sierra says more than 100.
Shopify and Muse
Shopify powers businesses in more than 175 countries, and every Shopify store supports Universal Commerce Protocol by default, the post says. Every Shopify store now automatically publishes a Poppy file, “so merchants don’t need to do any extra implementation”.
The post splits the work between the two: UCP handles the shopping itself, from finding products to checkout, while Poppy handles what happens before that, “when an agent shows up at a store, says who it is, and finds out what it’s allowed to do”. The commerce extension lets an agent shop as a guest or signed in, and makes it ask the customer before certain actions.
Who Is Live
Sierra names three partners going live. Mercury customers can ask a personal agent to check balances, categorize spending or initiate a payment, which goes through the account’s approval policy first. Turkish Airlines lets agents check fares and flight status, pull up bookings and find business-class upgrades that customers approve before paying. Synchrony is exploring financing in agent-led shopping across more than 500,000 merchant locations.
As we read the post, Sierra is placing Poppy in front of the checkout rather than replacing it: UCP handles finding products and checking out, while Poppy handles who the agent is and what it is allowed to do.
As we read the partner counts, the list has widened beyond commerce: the 60 new names include banks, insurers, airlines and software companies, from Navy Federal Credit Union and Travelers to Delta Air Lines and Zoom.
Bret Taylor and Clay Bavor, Sierra blog, 13 November 2026
“Poppy handles what happens before that, when an agent shows up at a store, says who it is, and finds out what it’s allowed to do”
Three Implications
FOR MERCHANTS Sierra says every Shopify store now publishes a Poppy file automatically, so merchants need no extra implementation.
FOR OTHER COMPANIES The post says any company can implement Poppy on its own with Sierra’s implementation kit and validator, and then serve customers who use Muse.
FOR OUR COVERAGE The specification is still labelled draft 1.0; we will report changes that are not backward compatible if Sierra publishes them.
The framework puts the contest one layer above the model: “It is about controlling the operating layer through which autonomous work is delegated, orchestrated, and governed.”
As we read it, Poppy is a bid to set the rules of that layer between personal agents and companies. The framework predates Poppy and does not discuss Sierra.
What Is Not Established
The specification itself is titled draft 1.0 and says it can still take fixes that “can include changes that aren’t backward compatible”; the protocol’s home page still described 0.4 as the 1.0 release candidate when we read it. Sierra gives no count of live companies beyond the three named, no Muse usage figures and no number of Shopify stores. The 43 and 103 partner totals are our arithmetic from Sierra’s counts.
This Week In The AI Supercycle
The Great Convergence of Capital, Power, and Geopolitics
This week’s issue: for two years the AI build-out was priced as a supply story, and last week as a credit story. This week it was priced as a permission story, and the answer arrived as a cost, not a ban.
Sierra’s Poppy 1.0 arrives with two large distribution points on day one: every Shopify store publishes a Poppy file, and Meta’s Muse looks for Poppy first on every site. Design partners rose from eight to more than 100 in 38 days, by our count.
A note on sourcing. We read Sierra’s release post of 13 November 2026 in full, its 6 October launch post with the 9 October update, and the draft 1.0 specification and home page at personalagentprotocol.org. Partner totals of 43 and 103 are our arithmetic from Sierra’s counts.
Gennaro Cuofano is a CRO and tech executive who has worked in AI since late 2015, starting with bringing NLP, natural-language generation, voice and chatbot products to the marketing industry. His background is in law and finance: he holds a Master's degree in Law and an International MBA with an emphasis on corporate finance (LUISS Business School and the University of San Diego, 2012), and worked as a financial analyst at a real-estate investment firm in San Diego and as an assistant controller. His work focuses on business model strategy, business engineering and, more broadly, structural analysis: how companies make money, read from their own filings. He created FourWeekMBA and leads research there and at The Business Engineer, his newsletter on AI and business strategy, with over 95,000 subscribers and more than 1,000 published analyses. His writing has also appeared on Entrepreneur (for example, How to Digitize a Family Business in Europe) and HackerNoon. Find him on LinkedIn and Substack. See how we source.
