schema · evergreen
Host, client, server
The host is the app, it holds one client per connection, each client talks to one server.
Three roles, and they are easy to blur. The host is the application. It holds one client per connection. Each client talks to one server.
| Role | Who writes it | What it owns |
|---|---|---|
| Host | the app vendor | the model, the UI, the approval prompts |
| Client | the SDK | one connection, protocol bookkeeping |
| Server | you | capabilities and the external system behind them |
The server is the only piece most people write. It exposes capabilities and does the talking to whatever sits behind it — a local database, a web API, a filesystem.