The Google Identity Toolkit API lets you use open standards to verify a user's identity.
curl \
-H "Authorization: Bearer $ACCESS_TOKEN" \
https://identitytoolkit.googleapis.com/v2/{name}curl \ -H "Authorization: Bearer $ACCESS_TOKEN" \ https://identitytoolkit.googleapis.com/v2/recaptchaConfig
curl \
-H "Authorization: Bearer $ACCESS_TOKEN" \
https://identitytoolkit.googleapis.com/v2/{parent}/tenants