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

# Authentication

> Publishable keys run in the browser, secret keys run on your server. How Filecheck keys and scopes work.

Filecheck uses two key types. Get both from the [dashboard](https://admin.filecheck.io).

| Key                 | Prefix                    | Where it runs                                    |
| ------------------- | ------------------------- | ------------------------------------------------ |
| **Publishable key** | `pk_live_…` / `pk_test_…` | In page JavaScript. Safe to ship in public code. |
| **Secret key**      | `sk_live_…` / `sk_test_…` | Server-side only. Never put it in browser code.  |

<Warning>
  Never expose a secret key (`sk_…`) in client-side code, a public repository, or a mobile app bundle. Use it only from your server.
</Warning>

## Test and live modes

`*_test_…` keys run against test data and never bill. `*_live_…` keys run in production. Swap the key prefix to switch modes; no other code changes are required.

## Agent ID (optional)

An **`agentId`** (`agt_…`) scopes the Element to a specific sub-tenant or store. This is useful when one Filecheck account powers multiple storefronts.

```js theme={null}
const fc = Filecheck('pk_live_…', { agentId: 'agt_…' });
```

## Using the keys

* **Publishable key** initializes the [Element](/element/installation) in the browser.
* **Secret key** authenticates server-side requests to the [API](/server/verify-jobs) with a bearer token:

```bash theme={null}
curl https://api.filecheck.io/jobs/{jobId} \
  -H "Authorization: Bearer sk_live_…"
```