I received a summons today from a debt collector. I am not working and have no income. I found the form "Application for Waiver of Court Fees". And "request for installments.

What I need is "a formal legal response" to the above summons.

My question... is there such a form? I am in the state of California

First its not a good idea to piggyback your question on someone else's. This can lead to confusion. You should start a new thread. So I've moved your question to its own thread.

Actually you don't need a "formal" response. There are dozens of threads here that detail what you need to do. You simply send a letter to the court stating your Intent to Defend the suit. You then send a copy of that letter to the plaintiff requesting verification of the debt.

If the court will be charging you fees as part of this suit, you can file your request to waive them.

But inability to pay is not a defense. If the plaintiff can prove the debt is yours they will obtain a judgment against you. However, they may not be able to use that judgment to collect if you have no income or assets. They may just sit on it until you do have income or assets they can attach.