Mo. Rev. Stat. § 77.600: Claims and suits for damages — notice.

No action shall be maintained against any city organized under the laws of this state as a city of the third class on account of any injuries growing out of any defect or unsafe condition of or on any bridge, boulevard, street, sidewalk or thoroughfare in said city, until notice shall first have been given in writing to the mayor of said city, within ninety days of the occurrence for which such damage is claimed, stating the place where, the time when such injury was received, and the character and circumstances of the injury, and that the person so injured will claim damages therefor from such city.