Mo. Rev. Stat. § 455.025
Except as provided under section 455.030, clerks under the supervision of a circuit clerk shall explain to litigants not represented by counsel the procedures for filing all forms and pleadings necessary for the presentation of their petition to the court. Notice of the fact that clerks will provide such assistance shall be conspicuously posted in the clerks' offices. The location of the office where a petition can be filed shall be conspicuously posted in the court building. The performance of duties prescribed in this section shall not constitute the practice of law as defined in section 484.010. All duties of the clerk prescribed in this section shall be performed without cost to the litigants. The supreme court may promulgate rules as necessary to govern conduct of court clerks under sections 455.010 to 455.085, and shall provide forms for petitions and written instructions on filling out all forms and pleadings necessary for the presentation of the petition to the court.
§ 455.025, RSMo