Newbie - verbal agreement binding without see written contract

[pc1980]

Hi I'm a newbie to it contracting.

Yesterday I got offered my first contract. The agency guy asked if I agree to the contract over the phone
when he gave high level details. I said yes but with the condition of seeing the written contract.

If I have issues with the written contract am I obliged to take the contract anyway?

I'm only concerned because a conversation with the agency guy later on yesterday he mentioned that the contract might have fixed working times (9 - 5:30) and thus have me inside IR35.

If they won't change the contract to total hours a week I would have to seriously reconsider taking the contract.

I know my mistake but got carried away with first contract.

Thanks in advance.