User Identifier

Attach your own user reference to a request so that risky events in the dashboard point back to a real person in your system.

The userID parameter#

Pass userID with any method. It can be a username, an email address, a phone number or your internal ID.

curl "https://gurdx.cretip.com/api/lookup/ip?key=YOUR_API_KEY&ip=1.1.1.1&userID=john@example.com"

curl "https://gurdx.cretip.com/api/scoring/email?key=YOUR_API_KEY&email=john@example.com&userID=u_48213"

The lowercase spelling userid is accepted as well.

What it is used for#

When a request raises an event (for example a suspicious IP or a spam email), the identifier is saved with the event. In the dashboard's events page you can then search by it, and webhook payloads carry it so your own systems can lock an account, ask for extra verification or open a review.

Rules#

• The value must be a single scalar and at most 255 characters. Longer or non-scalar values return error 123 invalid_userid.
• It is optional. Omit it if you have nothing useful to send.
• It is stored as text, so do not include secrets such as passwords or full card numbers.
• Test-mode requests never raise events, so the identifier has no visible effect there.

Payment requests#

For Payment Fraud Detection you do not need userID. The customer is identified from the data you already send, such as the customer email, phone or ID.

Choosing a good identifier#

Using the same identifier everywhere lets the dashboard group the events of one user across IP, email and phone checks.

Deleting user data#

If a person asks you to erase their data, use User Data Deletion, which removes records tied to an email, phone or user ID.

Tip: Hash personal identifiers (for example SHA-256 of the email) when you can. You keep the ability to match users without storing readable personal data at Gurdx.