Tex. R. Civ. P. 95
As amended through August 27, 2024
When a defendant shall desire to prove payment, he shall file with his plea an account stating distinctly the nature of such payment, and the several items thereof; failing to do so, he shall not be allowed to prove the same, unless it be so plainly and particularly described in the plea as to give the plaintiff full notice of the character thereof.
Tex. R. Civ. P. 95