If a Mediated Settlement Agreement (MSA) is reached and signed by the parties, it must be filed at the courthouse.
I encourage people to file a document at the courthouse (petition) before attending mediation -- so that there is a court of jurisdiction and a cause number.
The MSA must contain certain "magic" language to be enforceable and final. Normally it will states that this MSA resolves all disputes between the parties and "THIS AGREEMENT IS NOT SUBJECT TO REVOCATION" or similar language.
There are partial MSAs that resolve only some of the issues between the parties. If so, the MSA should clearly state what has been agreed to and what is still in disagreement. If this is done, the judge would only hear those issues NOT resolved at the mediation. This can save time and money by making your trial faster and limited.
All parties need to sign an "Agreement to Mediate" when they enter the mediator's office. This assures that the parties were given the "rules to mediate" and that they understand that if they come to an agreement that this is a final agreement and cannot be revoked at a later date.