# Quick start

A person completes steps 1 to 3. An agent can do steps 4 to 6 once it has an API key.

1. **Create an account** at https://zrouter.si/login?mode=signup with email and password (12 to 72 bytes), Google, or GitHub. Email sign-ups confirm their address first. New accounts start with $0 credit.
2. **Fund requests.** Buy $5 or more of prepaid USD credit under **Billing & credits** (Stripe Checkout), or save a provider key under **Bring your own keys** (see [BYOK](/docs/byok.md)).
3. **Create an account API key** under **API keys**. The secret is shown once. Give it to the agent through an environment variable such as `ZROUTER_API_KEY`.
4. **Pick a model.** Call `GET https://zrouter.si/v1/models` and use an `id` from the response, such as `PROVIDER_INSTANCE/MODEL_ID` or a virtual model name.
5. **Send a request:**

```bash
curl https://zrouter.si/v1/chat/completions \
  -H "Authorization: Bearer $ZROUTER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model": "PROVIDER_INSTANCE/MODEL_ID", "messages": [{"role": "user", "content": "Hello"}], "max_tokens": 256}'
```

6. **Check usage** with `GET https://zrouter.si/v1/usage`, or in the dashboard. The credit ledger is the source of truth for charges.

Next: [Authentication](/docs/authentication.md)