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

# Strails Mock Sandbox API Guide

> Lightweight isolated testing environment for integrating with the Strails API without triggering real transactions or exposing production secrets.

The Strails **Mock Sandbox** is a lightweight, isolated testing environment that mirrors the production API surface without triggering real blockchain transactions, KYC checks, or payment-provider flows. It is designed for fintech partners to:

* Integrate against API endpoints during development.
* Test request/response formats and error handling.
* Receive asynchronous webhook callbacks without exposing production secrets or funds.

| Environment | Base URL                         |
| ----------- | -------------------------------- |
| Test        | `https://sandbox.stablesrail.io` |
| Production  | `https://api.strails.io`         |

All endpoints are mounted under `/v1`:

```text theme={null}
POST https://sandbox.stablesrail.io/v1/onboarduser
```

### Important Notes

* **No real funds**: The sandbox does not interact with mainnet, testnet, or any custodial account.
* **No production secrets**: The sandbox uses its own parameter defaults (`SANDBOX_*`) and does not bind production values.
* **Webhook URL**: If a custom webhook is not configured, events are sent to the default `https://httpbin.org/post`.
* **Async mode**: Use `?mockMode=async` or `x-mock-mode: async` to trigger delayed webhook callbacks.