L402 Is Ready. The Missing Layer Is Adoption.
AI agents can write code, search the web, call APIs and coordinate increasingly complicated work. But when an agent needs to buy something, most of that autonomy stops.
Most card and subscription workflows assume an account, a provisioned credential or an established billing relationship. Those systems work well for ongoing relationships. They add friction when software discovers a new resource at runtime and needs to buy it immediately.
L402 offers a different model:
- An agent requests a resource.
- The server responds with
HTTP 402 Payment Required, a Lightning invoice and an authorization token. - The agent pays the invoice.
- Settlement reveals the payment preimage.
- The agent retries with the token and preimage.
- The server verifies the proof and returns the resource.
Settlement supplies the proof needed to activate the authorization token. An agent with a configured, funded wallet can purchase access without first creating an account or provisioning an API key with each seller.
The core primitive is ready. The surrounding adoption layer is not.