To authenticate, use a "REPLIERS-API-KEY" header and set the value to {API-KEY} with each request.
Here's an example CURL request that demonstrates Repliers API authentication using the REPLIERS-API-KEY header:
curl --request GET --url https://api.repliers.io/listings --header 'REPLIERS-API-KEY: {API-KEY}' --header 'content-type: application/json'
Your API-KEY is provided when your developer account is created.