I don't think there's much at agnes waters from what I could see. The main beach is your typical semi protected ocean kind of surf n chop. I'm sure other's have some better info on here

Although I haven't sailed it, 1770 looked like it would be a great spot. It's like a bigger and better version of noosa river mouth. Probably works best in NW to NE wind directions?

listery said..
Agnes Water beach has exposed beachrock which is underwater at mid tide. Shots taken from the Atlantis Blvd access

If i sail or kite on the main beach I usually launch from Surf Club avenue. Never had an issue with the rocks up there. Rocks aren't always that exposed.

There was a post way back 29th October 2007, titled " Sunshine Coast, Qld windsurfing spots". Mostly wave focus but identified some lake and flat water spots also.

I'm keen to do some similar trip around Sunshine coast later this year, travelling from NZ, probably with a 110 lit freeride board. So also keen to hear which are the popular spots.