You can test the integration with Copyleaks API for free using the sandbox mode. You will be able to submit content to scan and get back mock results, simulating the way Copyleaks will work.
To turn the sandbox mode on, add the http-header
copyleaks-sandbox-mode to your calls.
No matter what the value is.
Http Request headers:
Unlike the scans in production, the sandbox scans have a short lifespan and will expire after 24 hours and will be no longer avialble.
You can send up to 1,000 sandbox calls per day. Exceeding this limit will cause your account to be frozen.