# Testnet and devnet

URL: https://docs.hanzo.ai/docs/testnet

> Two copies of the Hanzo cloud that take only Square sandbox cards. Testnet runs exactly what production runs; devnet runs what is being built next, with accounts of its own.

**After this page you can point your code at a network where no card is ever
really charged, and know which one to pick.**

Hanzo runs three copies of the same cloud. Each has its own API, its own web app,
its own books and its own chain, and only one of them takes real money.

|             | API                         | Web app          | Sign-in         | Runs                                      | Money               |
| ----------- | --------------------------- | ---------------- | --------------- | ----------------------------------------- | ------------------- |
| **mainnet** | `https://api.hanzo.ai`      | hanzo.ai         | hanzo.id        | the current release                       | real cards          |
| **testnet** | `https://api-test.hanzo.ai` | test.hanzo.ai    | hanzo.id        | the same release as mainnet, always       | Square sandbox only |
| **devnet**  | `https://api-dev.hanzo.ai`  | app-dev.hanzo.ai | id-dev.hanzo.ai | the `dev` branch, minutes after each push | Square sandbox only |

> **Testnet is production's release, byte for byte.** Every release that reaches
> api.hanzo.ai reaches api-test.hanzo.ai in the same step, so a checkout or an
> integration that works on testnet works on mainnet. Use **devnet** to try what is
> coming before it is released.

## Pointing a client at a network

Every path is the same `/v1` as production. Change the base URL and nothing else.

```bash
curl https://api-test.hanzo.ai/v1/models
```

Testnet and devnet do not accept API keys: an `sk-` key authenticates on
mainnet only. Authenticate with an account token. Testnet takes your Hanzo
account's token, the one hanzo.id issues; devnet takes only a devnet account's
token, issued by id-dev.hanzo.ai (see [Signing in](https://docs.hanzo.ai/docs/testnet#signing-in)). `hanzo auth
token` prints the token for the network the CLI is on:

```python
import subprocess
from openai import OpenAI

token = subprocess.check_output(["hanzo", "auth", "token"], text=True).strip()
client = OpenAI(base_url="https://api-test.hanzo.ai/v1", api_key=token)
```

To aim the `hanzo` CLI at a network, select it; the API and the sign-in host
follow:

```bash
hanzo network use devnet    # api-dev.hanzo.ai, signing in at id-dev.hanzo.ai
hanzo auth login
hanzo network use mainnet   # back to api.hanzo.ai and hanzo.id
```

## Signing in

**Mainnet and testnet** share one identity: you sign in with your Hanzo account,
the one you use on hanzo.ai. What is separate is everything that account
_holds_: a testnet balance, card on file, invoice or usage record lives only on
testnet and is never mixed with your production books.

**Devnet has accounts of its own.** It runs code that is still being built, so it
never sees a production credential: its identity is id-dev.hanzo.ai, a token
from hanzo.id is refused at api-dev.hanzo.ai, and a devnet token is refused at
api.hanzo.ai. Sign in at id-dev.hanzo.ai, or on app-dev.hanzo.ai, with a devnet
account; your hanzo.id account does not exist there.

## Paying with a sandbox card

On test.hanzo.ai and app-dev.hanzo.ai/pay the card form is Square's **sandbox**. No real
card is accepted and none is charged; the credit you buy is testnet or devnet
credit and spends only there.

| Card       | Number                | CVV   | Expiry          | Postal code       |
| ---------- | --------------------- | ----- | --------------- | ----------------- |
| Visa       | `4111 1111 1111 1111` | `111` | any future date | any, e.g. `94103` |
| Mastercard | `5105 1051 0510 5100` | `111` | any future date | any               |

To test a decline, use either card with CVV `911`, postal code `99999` or expiry
`01/40`. A client that sends Square nonces directly uses `cnon:card-nonce-ok` and
`cnon:card-nonce-declined`. Square documents every sandbox value at
[developer.squareup.com/docs/devtools/sandbox/payments](https://developer.squareup.com/docs/devtools/sandbox/payments).

## What a sandbox network is not

- **Not a way to move real money.** It cannot be switched to live payments, and
  no real card, crypto deposit or payout rail exists on it.
- **Not paid models.** Testnet and devnet route Hanzo's free models only; a paid
  model id is refused.
- **Not a place to keep data.** Treat testnet and devnet data as disposable.
- **Devnet is the API, identity and checkout only.** It sends no email or SMS, so
  it signs in by password; it offers no social sign-in, no MPC wallets, no crypto
  deposits and no builds.