The agent prompt is part of the interface.
That is a strange little shift.
A button is not only a button.
A prompt is not only copy.
It tells the agent what to read.
What to respect.
What not to infer.
What routes matter.
What kind of response would be useful.
That makes it interface design.
Not visual design.
Context design.
If someone wants their agent to understand a person or company, the handoff matters.
The prompt becomes the bridge between the public surface and the agent’s interpretation of it.
That bridge should be designed.