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

# Environment variables

> Give your app its API keys without putting them in the code.

Apps often need keys: a Supabase URL, a Stripe publishable key, an API endpoint. Keep them in your project's environment variables instead of in the code.

## Add a variable

**1. Open Env**

Click **Env** in the project's top bar.

**2. Pick the scope**

**Development** is used by the preview, **Production** by production builds.

**3. Save it**

Enter the name and value, and save.

Values are encrypted when they're stored. After saving, the list shows only names and a fingerprint, never the value. Only workspace admins can reveal a value, and every reveal is logged.

## Public and secret

The name decides who can see a value:

| Name | Visibility | Where it goes |
| - | - | - |
| `EXPO_PUBLIC_*` | **Public.** Expo puts it in the app's bundle, so anyone with the app can read it. | The preview and your builds |
| Anything else | **Secret.** Never given to the agent or the preview. | Your native builds only |

> [!WARNING]
>
> Only use `EXPO_PUBLIC_` names for keys that are meant to be public, like a publishable key. Appnetic warns you if a public value looks like a secret.

## When the agent needs a key

The agent sees variable names, never their values. If it needs a key you haven't added, it asks in the chat: paste the value into the card and save, or dismiss it. The request also shows in the Env drawer.


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