# Consumer guide

CommandKit's supported Go API is the root `commandkit` package. Start with an
`App`, register CommandKit's standard inspection families, register application
commands, and call `App.Execute` with the caller's context and streams. The
caller retains process startup, signal handling, and exit mapping.

## A configuration scope

Use [`NewConfigKitScope`](../../config.go) to adapt one ConfigKit loader. The
loader receives the invocation's explicit `Selection`; the application decides
how those supplied config and overlay values map to its inputs.

```go
scope, err := commandkit.NewConfigKitScope[appContext, appConfig](
	"app",
	"Application settings.",
	func(ctx context.Context, selection commandkit.Selection, app appContext) (*configkit.Result[appConfig], error) {
		return loadAppConfig(ctx, selection, app)
	},
)
if err != nil {
	return err
}
err = commandkit.RegisterConfig(app, commandkit.ConfigSuite[appContext]{
	Scopes: []commandkit.ConfigScope[appContext]{scope},
})
```

`config show`, `config sources`, and `config explain` use the configuration
captured by that load. A scope can support only the operations it provides.
When several scopes share invocation-local application state, create it in
`ConfigSuite.NewContext`; use typed `Selector` bindings to copy only the values
that apply to each scope. See the [composed example](../../examples/composed/README.md)
for a cache shared by the `app` and `promptkit` scopes.

## PromptKit configuration and definitions

Register `NewPromptKitScope` with the config suite when you want the effective
PromptKit configuration and its ConfigKit provenance available under `config`.
Register `NewPromptKitSuite` and `RegisterPromptKit` separately to enable
`promptkit show prompt` and/or `promptkit show profile`. Each adapter calls the
owning public inspection method and preserves acquisition diagnostics with a
failed named lookup. Definition inspection does not invoke execution APIs or
resolve provider credentials.

The [composed example](../../examples/composed/README.md) shares its ordinary app and
engine-loading functions across the configuration and definition suites. It
also keeps `session restore` as an application-owned typed command, including
its session data and domain outcome mapping.

## Typed application commands

Declare flags, operands, and a typed input struct with `NewCommand`. Bindings
preserve whether a value was explicitly supplied, so an explicit zero can differ
from an omitted default. `RepeatFlag` retains occurrence order. The
[simple example](../../examples/simple/README.md) combines both features with a typed
ConfigKit scope.

## Outcomes and process exit

Handlers return `Success`, `Failure`, or an application-owned `Outcome`. The
caller chooses how a nonzero status maps to process exit; `Execute` never exits
the process. It writes CommandKit diagnostics to the supplied error stream and
returns the resulting classification and delivery information. Applications
keep their domain meanings and output in their own handlers.

Exact CommandKit contracts are documented on the exported declarations and
their GoDoc comments. ConfigKit owns configuration decoding and provenance;
consult its [inspection API](https://gitea.maximumdirect.net/eric/ConfigKit/src/commit/dc09959cca4e105f49ec316c6d4ba585bd2340bd/inspection.go).
PromptKit owns prompt formats and profile resolution; consult its [public
engine methods](https://gitea.maximumdirect.net/eric/promptkit/src/commit/4b8169da286917fde7875425bb32b799b12c6af3/engine.go),
[configuration inspection](https://gitea.maximumdirect.net/eric/promptkit/src/commit/4b8169da286917fde7875425bb32b799b12c6af3/configuration_inspection.go),
and [inspection types](https://gitea.maximumdirect.net/eric/promptkit/src/commit/4b8169da286917fde7875425bb32b799b12c6af3/types.go).