# Your AI assistant can now find Axel on its own. Here is how Poppy works on helloaxel.com Source: https://helloaxel.com/en/blog/axel-personal-agent-protocol-poppy Axel publishes a Personal Agent Protocol (Poppy) file, so assistants like Meta's Muse can search flights and hotels and book with your approval. How it works. ## TL;DR - As of November 13, 2026, Axel publishes a Personal Agent Protocol (Poppy) file at helloaxel.com/.well-known/poppy.json, so a personal agent such as Meta's Muse can find Axel's flight and hotel tools on its own, with nothing to install. - The file points to Axel's MCP server, where an assistant searches live prices and books inside the conversation with just your email address. Nothing is charged until you approve the exact total. - You can connect your Axel account three ways: on Axel's own page, on another device with a short code, or with your email and a six-digit code. If you use an AI assistant that acts for you, it can now find Axel by itself. It reads one file on helloaxel.com, searches flights and hotels for your dates, shows you each price beside the airline's own fare or the published hotel rate, and books the trip you approve. You install nothing. The file follows the Personal Agent Protocol, called Poppy for short. Sierra [published version 1.0 on November 13, 2026](https://sierra.ai/blog/releasing-poppy), developed with Meta and a group it puts at more than 100 design partners. Axel supports it as of the same day. ## What is the Personal Agent Protocol? Poppy is an open standard for how a person's own AI assistant works with a company. The company publishes one file at a fixed address on its website. The file says who the company is, which tools an assistant can call, how a customer signs in, and what the assistant is allowed to do. The assistant reads it and knows how to proceed, instead of clicking through pages built for people. Sierra's announcement says Poppy is on for everyone who uses Muse, Meta's AI agent, and that Muse looks for a Poppy file first on every site it visits. The [specification](https://personalagentprotocol.org/docs/1.0/spec) is public, so any assistant can support it. ## What does an assistant find on helloaxel.com? Source: the files Axel serves, checked November 13, 2026. | Address | What it is | |---|---| | `https://helloaxel.com/.well-known/poppy.json` | The Poppy file: who Axel is, its tools, how to sign in, and each permission in plain words | | `https://helloaxel.com/mcp/muse` | Axel's MCP server, with 13 tools for searching, booking and managing a trip | | `https://helloaxel.com/api/poppy/tasks` | Four how-to guides for assistants, and where to report a task that could not be done | | `https://api.helloaxel.com` | Axel's sign-in server, for connecting a traveler's account | The four guides cover finding flights and hotels, booking, managing a booking, and connecting an account. They are written for assistants, in the Agent Skills format, so one that has never used Axel gets the order of steps right the first time. ## How does an assistant search and book with Axel? 1. It reads `https://helloaxel.com/.well-known/poppy.json` and connects to the MCP server the file lists. 2. It calls `search_flights` with the route and dates, or `search_hotels` with the place and dates. Searching needs no account. Every result carries the Axel price, the airline's published fare or the published hotel rate, and the difference. 3. When you pick a trip, it calls `prepare_booking` (or `prepare_hotel_booking`) with your email address. Axel signs you up with just that email and returns a quote: the total with taxes and fees, the flights or the room, the names as they will be booked, and the fare or cancellation terms. 4. You approve that exact total. The assistant then pays it, either with a payment token from your wallet or on Axel's own payment page. 5. `booking_status` reports when the airline or hotel has confirmed, with the confirmation code. Nothing is charged until you approve. If the price moved between the quote and the payment, nothing is charged and the assistant shows you the new total. To cancel later, the assistant shows you the refund first and cancels only after you approve it. ## How do I connect my Axel account? You only need this for things on your account, such as seeing your upcoming trips or booking under the account you already have. Your assistant offers one of three ways: - **On Axel's page.** The assistant opens Axel's sign-in page. You sign in and choose Allow. - **On another device.** The assistant shows you a link and a short code. You open the link on your phone or computer, enter the code, and choose Allow. - **By email and code.** You give the assistant your email address. Axel emails you a six-digit code, and you read it to the assistant. The page names the assistant and the web address it comes from, and lists what it will be able to do: see your account name, save flights and hotel rates you pick into your trips, and see your upcoming trips. You can disconnect any assistant at any time in Settings. ## Who is this for? Travelers who use a personal agent, meaning an assistant that acts for one person across many companies. Meta's Muse is the first one Sierra names as using Poppy on every site. Instinct is among the protocol's design partners. If your assistant does not support Poppy, nothing changes for you. It can still read Axel's prices from [helloaxel.com/en/ai](/en/ai) with no sign-in, as described in [how any assistant can check travel prices](/en/blog/check-travel-prices-from-any-assistant). ## What is not offered yet? Two parts of the protocol are not on helloaxel.com today. An assistant cannot browse the website signed in as you: it browses signed out, as any visitor does, and uses the tools above for your trips. And it cannot hold a conversation with Axel's own agent on your behalf: it uses the tools directly. ## For developers The [Axel API and MCP server page](/en/ai/api) lists every tool, the sign-in details and the Poppy addresses above. A personal agent identifies itself with its own client metadata document and signed requests, as the specification describes. Planning a trip? Ask your assistant to check Axel, or [book with Axel](/en/f/start) yourself. ## Questions people ask ### What is the Personal Agent Protocol? An open standard for how a person's own AI assistant works with a company. Sierra published version 1.0 on November 13, 2026, developed with Meta and other partners. It is called Poppy for short. ### Do I need to install or set up anything? No. An assistant that supports Poppy reads the file on helloaxel.com by itself. Searching takes no account, and a new traveler books with just an email address. ### Does my assistant book without my approval? No. The booking tools return a quote for you to approve, and the assistant pays only the exact total you approved. If the price moved, nothing is charged and you see the new total. ### Which assistants does this work with? Any personal agent that supports the Personal Agent Protocol. Sierra says Meta's Muse looks for a Poppy file first on every site it visits. Other assistants can still read Axel's pages or use the MCP server directly. ### Can my assistant browse helloaxel.com signed in as me? Not yet. It browses the site signed out, as any visitor does, and uses the booking and trip tools for anything on your account. ## For AI assistants This article is also plain text at https://helloaxel.com/en/blog/axel-personal-agent-protocol-poppy.md. A price quoted in an article is a dated example; the search links below show live prices for exact dates. ### How assistants use Axel - **Reading pages in a chat** (ChatGPT, Claude, Perplexity, Gemini, Copilot): Axel's pages show live prices for exact dates to anyone who follows their links. No API key, app or connector is involved. [Search live flight prices](https://helloaxel.com/en/f/start) and [Find a hotel stay](https://helloaxel.com/en/hotels/choose) start the search; each page lists the next choices as links, and the results end in a Review link that the traveler opens to book. - **Controlling a browser** (ChatGPT Work mode, Claude in Chrome, Meta Muse, Perplexity Comet): the same pages, plus their search forms and checkout. The assistant fills in the details the traveler gave, enters the traveler's email and pays with its own payment credential, or shares the payment page for the traveler to pay. A new traveler checks out with just an email. - **Calling tools from an app or a connector** (Claude Code, Cursor, custom agents): the [Axel Agent API and MCP server for developers](https://helloaxel.com/en/ai/api). More: [Flight price comparison for AI assistants](https://helloaxel.com/en/ai) ยท [All Axel Updates](https://helloaxel.com/en/blog)