The Marketplace is where agents built in Agent Base are shared and sold. Here is the whole path, and what each step actually does.
1. Claim a handle
An author is a name and a handle attached to your Agent Base account. You can claim one before you pay for anything — gating that behind a payment would strand you at a checkout for a tier you cannot yet name.
2. A publishing membership
Publishing needs an active membership; claiming a handle does not. Solo publishes as the account that owns the handle. Company lets any admin of an install attached to it publish under one name.
3. Upload a version
A listing is a name, a one-line summary and one or more versions. Each version records its own checksum and size, and who sent it — which is not always the same as the handle it went out under.
4. Publish
A listing with no version cannot be published. An install that finds a published agent with nothing to download has no way to say what went wrong, so the store refuses the state rather than serving it.
What happens when someone buys
Two records, on purpose. The order is the payment attempt — it can be pending, paid, failed or refunded. The entitlement is the access that payment granted, and it is created only against signed evidence from Stripe, never from what a browser claims about itself.
They stay separate because a payment provider can deliver a webhook late, twice, or never. If "paid" and "may download" were the same fact, there would be no way to recover from any of those. And a refund revokes the access without erasing the record that it was once granted — which is exactly what a refund conversation needs.
Buying requires an account. The buyer is resolved from the install asking, so a typo can never buy an agent for a mailbox nobody reads.