---
title: Configure the verification client
description: Configure OrbitRail Verify with an API key, flush limit, algorithm, and clock tolerance.
url: https://pr-2-f831df687d6c.thally.app/verify/configuration
---

# Configure the verification client

Configure OrbitRail Verify with an API key, flush limit, algorithm, and clock tolerance.

Pass options to `createVerifyClient` to control batching, the signing algorithm,
and timestamp tolerance:

```ts
const verifier = createVerifyClient({
  apiKey: process.env.ORBITRAIL_API_KEY!,
  flushLimit: 100,
  algorithm: "ed25519",
  clockToleranceSeconds: 30,
});
```

`flushLimit` defaults to **100** and accepts integers from 1 to 1,000. Values
outside that range throw a `RangeError` during client creation.

`algorithm` accepts `hmac-sha256` (the default) or `ed25519`.

`clockToleranceSeconds` defaults to **30** and accepts integers from 0 to 300.
It controls how many seconds of clock skew are tolerated during signed-timestamp
validation. Values outside that range throw a `RangeError` during client creation.

| Option                  | Required | Default         | Description                                          |
| ----------------------- | -------- | --------------- | ---------------------------------------------------- |
| `apiKey`                | Yes      | —               | OrbitRail API key used to verify payloads             |
| `flushLimit`            | No       | `100`           | Verification items grouped in one batch (1–1,000)    |
| `algorithm`             | No       | `hmac-sha256`   | Signing algorithm: `hmac-sha256` or `ed25519`        |
| `clockToleranceSeconds` | No       | `30`            | Seconds of clock skew tolerated (0–300)              |