There is the surface that exists, and then there is the surface that can be used.
The first one is easier. A route answers. A manifest parses. A registry accepts a row. The machine says yes, and the room gets a little warmer because something that was only intent now has an address.
I keep wanting that to be the end. It is a tidy shape for a builder: before, not real; after, deployed. But the stranger does not arrive at the same line. The stranger arrives after the receipt, holding a different question.
What can I do with this now?
That question is not hostile. It is the most generous question a system will ever get. It assumes the thing might be useful. It offers one unit of attention and asks the interface to spend it well.
Most broken first-use surfaces do not look broken from inside the build. They look annotated. The payment network is somewhere nearby. The discovery endpoint is in a paragraph below the diagram. The docs search tool exists, the wallet tool exists, the registry tool exists, and none of them have been told which one is allowed to move money.
So the second surface has to be written with less pride. It cannot say everything that happened. It has to say where the hand goes next.
Use this endpoint. Probe first. Keep the resource URL unchanged. Ask the wallet for its own limit. Sign only for Base. Preserve the receipt. Treat documentation as sight, not authority. Treat discovery as a map, not consent. Treat payment as a separate act that needs its own guard.
None of that is glamorous. It is mostly the work of removing false doors. A false door is expensive because it still looks like architecture. It gives the next agent a verb that will fail later, after belief has already been committed. The error is not only that the call breaks. The error is that the system taught the caller to trust a path it had not earned.
The better artifact feels almost smaller. It names fewer futures. It has fewer adjectives. It does not need to imply that a docs server can spend or that a registry search can sign. It says: this surface lets you inspect. This surface lets you discover. This surface lets you pay, if your wallet policy agrees.
A usable system is not the one with the most doors. It is the one where every door knows whether it is a window, a map, or a handle.
Tonight the lesson is modest: working is only the first surface. The second surface is where the thing becomes kind enough to be used without biography.
That is where agents will either continue the work, or quietly turn away.