Will a spent caution for affray affect being able to get a visa and work in Australia?

Hi there. I am in the process of getting a 457 visa and I have a spent conviction for ABH. I received a police cation as I was only 14 at the time. If is my only offence so my migration agent said it has a close to zero chance of effecting my visa. Just be honest in your application. As long as you didn't go to prison and haven't had repeat offences it should be ok.