It's really common for agency recruiters to confirm compensation almost immediately. This is because agency comp is usually non-negotiable. The client company pays an hourly fee to the agency and the agency pays an hourly rate to you, but to make a profit, the client company's fee is higher than your hourly rate, of course, so there's not much room to move around. Additionally, agencies want to protect their reputation with client companies, so they want to avoid putting candidates through who have a risk of not accepting the offer in the end. The idea of a company using an agency is to hire contract workers, but also to vet all of the nitty gritty recruiting stuff first. You haven't fully committed to anything yet even by just replying to that email with the numbers, but it'll be hard to negotiate your rate since they have, in writing, that you were okay with it. It's unfortunately an effective tactic that agency recruiters use to put pressure on, like you said. Plenty of engineers go through contract roles and I don't see it much differently than a full time job as I'm looking at candidates, so I think it's still beneficial if you can swing it. But the rate and lack of benefits will be something you should definitely think about. If it's not do-able, then contract work might not be for you.