Tex. Gov't Code § 418.117

If the assistance of a person who holds a license, certificate, permit, or other document evidencing qualification in a professional, mechanical, or other skill is requested by a state agency or local government entity under the system, the person is considered licensed, certified, permitted, or otherwise documented in the political subdivision in which the service is provided as long as the service is required, subject to any limitations imposed by the chief executive officer or the governing body of the requesting state agency or local government entity.