Mo. Rev. Stat. § 545.240: Informations — how filed, verified.

Informations may be filed by the prosecuting attorney as informant during term time, or with the clerk in vacation, of the court having jurisdiction of the offense specified therein. All informations shall state the name of the prosecuting attorney and be verified by his oath or by the oath of some person competent to testify as a witness in the case, or be supported by the affidavit of such person, which shall be filed with the information; the verification by the prosecuting attorney may be upon information and belief; all in the manner provided by supreme court rule. The names of the witnesses for the prosecution must be affixed to the information, in like manner and subject to the same restrictions as required in case of indictments.