Harris County has some pretty comprehensive information on its court website.
http://www.jp.hctx.net...
The information provided cites the statutes and rules that apply.
You can look them up at:
http://caselaw.lp.find...
Here is the small claims statute:
http://caselaw.lp.find...
According to the website:
"Reasonable discovery in Small Claims Court is limited to that considered appropriate and permitted by the judge. See Section 28.033, Texas Government Code."
You basically have two choices. Give the attorney what he wants or file a motion with the court to limit what you have to give to the attorney and see how that goes.
Before you do that, though, you might explain what your case is about, how much you are suing for, and what the attorney is requesting.
We might be able to tell you whether it's "appropriate" and guide you through the legalese.