A more thorough explanation:

Definition: Libellus conventionis is a Latin term used in Roman law. It refers to the statement of a plaintiff's claim in a petition sent to the magistrate, who directs its delivery to the defendant. It is similar to the modern statement of claim, as it sets forth the nature of the plaintiff's right and the circumstances surrounding its alleged violation.

Example: If a person believes that their neighbor has trespassed on their property, they can file a libellus conventionis with the magistrate. The libellus conventionis would state the nature of the plaintiff's right to the property and the circumstances surrounding the alleged trespass.

Explanation: This example illustrates how a libellus conventionis would be used in a real-life situation. The plaintiff would use this document to formally state their claim and provide evidence to support it. The magistrate would then deliver the document to the defendant, who would have the opportunity to respond to the claim.