[Home](./index.md) > [@firebase/auth](./auth.md) > [ActionCodeOperation](./auth.actioncodeoperation.md) ## ActionCodeOperation enum An enumeration of the possible email action types. Signature: ```typescript export declare const enum ActionCodeOperation ``` ## Enumeration Members | Member | Value | Description | | --- | --- | --- | | EMAIL\_SIGNIN | "EMAIL_SIGNIN" | The email link sign-in action. | | PASSWORD\_RESET | "PASSWORD_RESET" | The password reset action. | | RECOVER\_EMAIL | "RECOVER_EMAIL" | The email revocation action. | | REVERT\_SECOND\_FACTOR\_ADDITION | "REVERT_SECOND_FACTOR_ADDITION" | The revert second factor addition email action. | | VERIFY\_AND\_CHANGE\_EMAIL | "VERIFY_AND_CHANGE_EMAIL" | The revert second factor addition email action. | | VERIFY\_EMAIL | "VERIFY_EMAIL" | The email verification action. |