get https://sandbox.lithic.com/v1/three_ds_decisioning/secret
Retrieve the 3DS Decisioning HMAC secret key. If one does not exist for your program yet, calling this endpoint will create one for you. The headers (which you can use to verify 3DS Decisioning requests) will begin appearing shortly after calling this endpoint for the first time. See this page for more detail about verifying 3DS Decisioning requests.