> ## Documentation Index
> Fetch the complete documentation index at: https://docs.astilba.com/llms.txt
> Use this file to discover all available pages before exploring further.

# astilba check (CLI)

> The astilba CLI that catches i18next translations which silently break interpolation, across every locale, in CI or locally.

`astilba check` validates that every locale keeps its placeholders intact. When a translator
(or a machine) renders `"You have {{count}} items"` as `"Vous avez des articles"`, the
`{{count}}` is gone and i18next fails silently at runtime. `check` finds that — across every
locale, in CI or locally — on top of the [`@astilba/core`](/reference/core-api) fidelity engine.

It ships as the [`astilba`](https://www.npmjs.com/package/astilba) package (MIT), a
self-contained bin bundling `@astilba/core` and the i18next adapter — no runtime dependencies.

## Usage

Zero-config: with no path it looks in `public/locales`, `src/locales`, `app/locales`, then
`locales`. Pass a directory to be explicit:

```sh theme={null}
npx astilba check ./locales --source en
```

## What it reports

* **Translation problems** — a target locale dropped, added, or changed a placeholder relative
  to the source (`{{count}}`, `$t(ref)`, `<b>…</b>`). This is the one tier that fails the build.
* **Unsupported source syntax** — ICU (`{n, plural, …}`); native i18next v4 renders it
  literally. A capability notice, not a translation bug.
* **Untranslated keys** — present in the source, missing in a target (falls back to source).
  CLDR-plural-aware: a target with fewer plural categories than the source (e.g. Japanese,
  whose only cardinal category is `other`) is **not** flagged for omitting `items_one`.

## Exit codes

| Code | Meaning                                                              |
| ---- | -------------------------------------------------------------------- |
| `0`  | No broken placeholders (clean, or warnings only)                     |
| `1`  | At least one translation problem                                     |
| `2`  | Usage error (no command, no locales found, unknown source locale, …) |

## Options

| Flag                     | Description                                                            |
| ------------------------ | ---------------------------------------------------------------------- |
| `--source <lang>`        | Source locale to compare against (default: `en`)                       |
| `--strict`               | Also fail (exit 1) on unsupported syntax and untranslated keys         |
| `--quiet`                | Hide the per-locale lines for clean locales (untranslated still shown) |
| `--json`                 | Machine-readable, `version`-tagged report                              |
| `--color` / `--no-color` | Force color on or off (default: auto — color on a TTY)                 |
| `-h`, `--help`           | Show help                                                              |

## In CI

```yaml theme={null}
- run: npx astilba check
```

A non-zero exit fails the job, so a dropped placeholder blocks the merge.

## Limitations (Phase 0)

`check` flags the forward direction — a target that drops a plural form the source language
requires. It does **not** yet flag the reverse — a target missing a plural category its *own*
language needs but the source language lacks (there is no source key to compare against). A
custom i18next `keySeparator` is also not configurable yet (keys are flattened with `.`).