Use the alloy-sandbox-use-webhooks header to test how your integration handles an asynchronous service without making live third-party vendor calls.
Test an asynchronous request
Send your Sandbox evaluation or Journey Application request with both headers:
alloy-sandbox: true
alloy-sandbox-use-webhooks: true
The request must follow a path that reaches an asynchronous service. The initial response will remain pending while Alloy waits for the simulated callback.
In the response headers, copy the value of alloy-sandbox-webhook-post-endpoint. This is the Sandbox URL used to simulate the service callback.
Send a second POST request to that URL using the same authentication. Use an empty request body and include:
alloy-sandbox: true
Check the evaluation or Journey Application status, or wait for your configured Alloy webhook. The pending request should continue and return its final result.
This header is intended for Sandbox testing only. It does not make live vendor calls or change production behavior.