Tex. R. Civ. P. 684
In the order granting any temporary restraining order or temporary injunction, the court shall fix the amount of security to be given by the applicant. Before the issuance of the temporary restraining order or temporary injunction the applicant shall execute and file with the clerk a bond to the adverse party, with two or more good and sufficient sureties, to be approved by the clerk, in the sum fixed by the judge, conditioned that the applicant will abide the decision which may be made in the cause, and that he will pay all sums of money and costs that may be adjudged against him if the restraining order or temporary injunction shall be dissolved in whole or in part.
Where the temporary restraining order or temporary injunction is against the State, a municipality, a State agency, or a subdivision of the State in its governmental capacity, and is such that the State, municipality, State agency, or subdivision of the State in its governmental capacity, has no pecuniary interest in the suit and no monetary damages can be shown, the bond shall be allowed in the sum fixed by the judge, and the liability of the applicant shall be for its face amount if the restraining order or temporary injunction shall be dissolved in whole or in part. The discretion of the trial court in fixing the amount of the bond shall be subject to review. Provided that under equitable circumstances and for good cause shown by affidavit or otherwise the court rendering judgment on the bond may allow recovery for less than its full face amount, the action of the court to be subject to review.
Tex. R. Civ. P. 684