Guides

Authentication

Send your API key in the X-API-KEY header on every request:

Code
GET /api/v1/user HTTP/1.1
Host: api.gmjroaming.com
X-API-KEY: your-api-key
Accept: application/json

Response	Meaning
`401` `{"message":"API key is missing"}`	No `X-API-KEY` header.
`403` `{"message":"Invalid API key"}`	The key is wrong or was rotated.

Your key can spend your balance. Keep it on your server. Never put it in a mobile app, browser code or a public repository. If it leaks, rotate it in the console right away.

Every request acts on the account that owns the key. You can only see and manage eSIMs and transactions that belong to that account.

Last modified on November 10, 2026

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