Discovery generally begins after the defendant files an answer, the parties hold a discovery planning conference, and the judge issues a scheduling order. All documents must be filed electronically with the Harris County District Clerk.Documents should not to be hand-delivered or faxed directly to the court. Copies – Once the documents are complete, make one copy for each party in the case. 2. Customer: I was served for interrogatories and documents. I will send you the filings and ask your advice on how to fill them out. A party may serve on any other party no more than 25 written interrogatories, including all discrete subparts. A party may propound interrogatories at any point up to thirty (30) days before the end of the discovery period. CV-Certificate of Service (Service of Papers Other than Citation). An interrogatory is a written question from one party to the lawsuit to another party to the lawsuit (usually, the opposing party).