Is it permissible to invoke blessings upon the angels in the Tashahhud, in the same way that blessings are invoked upon the Prophet (peace be upon him)?

Praying upon the angels in the Tashahhud is not prescribed because what is obligatory is to limit oneself to what has been reported from the Prophet (peace and blessings be upon him), and the prayer in the Tashahhud is limited to what has been reported. However, the worshiper's saying: "Peace be upon us and upon the righteous servants of Allah" includes the angels, for they are among the righteous servants of Allah.