# Collections

> For the complete documentation index, see [llms.txt](/llms.txt)

A **collection** is a named set of scenarios you run together — typically
`smoke` (fast, key flows) and `regress` (the full sweep).

## Run a collection

```sh
npx @unotest/web collection smoke --workers=4
```

| Flag | Effect |
| --- | --- |
| `--workers=N` | run N scenarios in parallel (default: serial) |
| `--bail` | stop after the first failure |
| `--headed` | run with a visible browser |

## In the viewer

The [viewer](/viewer/overview/) manages collections visually: create, rename,
reorder by drag, and run the whole set. During a run you see **per-scenario
status**, a progress bar, and a one-click **abort**.

## In CI

Collections are the natural CI unit — run `smoke` on every push, `regress`
nightly. See [Run in CI](/guides/ci/).