# How we got to the Personal Agent Protocol

> Meta launched Muse on September 8, 2026. Amazon blocked it on September 20. On October 6, Sierra and Meta announced the Personal Agent Protocol. The v0.1 spec is still pending.

Source page: https://pap.md/timeline  
Last checked against sources: Oct 8, 2026  
pap.md is independent and not affiliated with Sierra, Meta or any PAP partner.

| Date | Event | Detail | Source |
| --- | --- | --- | --- |
| Sep 29, 2025 | OpenAI and Stripe release the Agentic Commerce Protocol | ACP powers Instant Checkout in ChatGPT. Stripe issues a shared payment token so the agent never sees the card. Stripe is now also a PAP launch partner. | [Stripe](https://stripe.com/newsroom/news/stripe-openai-instant-checkout) |
| Oct 14, 2025 | Visa and Cloudflare introduce the Trusted Agent Protocol | TAP lets merchants tell a known agent from an anonymous bot by checking signed HTTP requests, building on Web Bot Auth. | [Visa Developer](https://developer.visa.com/capabilities/trusted-agent-protocol/docs-getting-started) |
| Nov 2025 | Amazon sues Perplexity over its shopping agent | Perplexity called the suit a bullying tactic. It set the tone for how big retailers treat agents that show up uninvited. | [CNBC](https://www.cnbc.com/2026/10/06/meta-joins-companies-to-tame-chaos-of-doing-business-with-ai-bots.html) |
| Jan 11, 2026 | Google announces the Universal Commerce Protocol | UCP covers the shopping flow from discovery to checkout and post-purchase. Shopify helped build it. | [Google Developers Blog](https://developers.googleblog.com/en/under-the-hood-universal-commerce-protocol-ucp/) |
| Sep 8, 2026 | Meta launches Muse | Meta’s personal agent books trips, fills in forms and buys things for its users, in the US first. | [Engadget](https://engadget.com/2253133/meta-reveals-its-ai-agent-that-can-shop-send-emails-and-plan-trips-on-your-behalf/) |
| Sep 20, 2026 | Amazon blocks Muse on Amazon.com | Amazon says Meta declined to remove Amazon from the Muse experience, and that the agent didn’t identify itself while browsing. | [BERI](https://www.beri.net/article/meta-sierra-personal-agent-protocol-oauth-guest-read-write-access-vs-ucp-acp-trusted-agent-protocol-retail-banks) |
| Oct 6, 2026 | Sierra and Meta announce the Personal Agent Protocol | Unveiled at Sierra Summit in San Francisco. OAuth sessions, guest or signed-in, read-only or write access, and three routes the company can offer. | [Sierra (Bret Taylor, Clay Bavor)](https://sierra.ai/blog/introducing-personal-agent-protocol) |
| Oct 6, 2026 | Two partner lists, not one | Sierra names Genesys, Instinct, Rocket, Shopify, Stripe and Walmart. Meta’s list swaps Instinct for NiCE and Decagon. | [CMSWire](https://www.cmswire.com/contact-center/genesys-joins-sierra-meta-on-open-standard-for-personal-ai-agents-01/) |
| Oct 6, 2026 | Decagon open-sources PACT and joins the PAP working group | PACT, built with Instinct on A2A and OAuth 2.0, ships with a public spec the same day PAP is announced without one. | [Decagon](https://decagon.ai/blog/introducing-the-personal-agent-consent-trust-protocol-pact) |
| Oct 2026 | PAP v0.1 specification (expected) | Promised for later in October, followed by design workshops and a reference implementation. | [Sierra (Bret Taylor, Clay Bavor)](https://sierra.ai/blog/introducing-personal-agent-protocol) |