Chat looks like the simplest interface in the world and is one of the hardest.
A blank input tells the user nothing about what the system can do. Latency is visible in a way it is not elsewhere. Long answers become walls that cannot be scanned.
The interface lives in the gaps
Entry, waiting and formatting decide whether a conversational product feels capable or vague.
Work on the seams rather than the bubbles.
Entry points that suggest capability without prescribing it, waiting states that make latency legible, and formatting that gives long responses structure.
Capability without a menu
Suggest what is possible without limiting it.
Entry points hint at range rather than listing commands, so discovery happens without turning an open interface into a form.
Legible waiting
Streaming and pending states designed, not defaulted.
Waiting is understood rather than endured when the interface shows that something is happening and roughly what stage it is at.
Correction inside the message
Retry and feedback where the content is.
Fixing a bad answer happens at the answer rather than in a menu, which is the only place a user thinks to look.
A surface where capability is discoverable.
The patterns generalise to any model-backed conversational product, which is why they carried into later AI work.