I carry loads of tools, but it all depends on location as where I cycle it's away from a bus service and away from family so no lift is available, so I have become self reliant and it all fits in a small zip up case and a very small drybag.
1 P*ncture repair kit
1 allan keys
1 set of tyre levers + 2 spare
3 inner tubes
Folding tyre
Tyre patches
1 small head torch in winter
marigold gloves
Small length of chain (3 inches)
1 small chain tool
Cassette tool and chain whip
Spare spokes
Kevlar spoke
hypercracker
Spare nuts, bolts, powerlinks
Wire cutters
Pliers
2 small screw drivers
Small sockets to fit screw driver handle
First aid kit with triangular bandage paracetamol, co-codamol, gaviscon tablets
Batteries for rear light and computer
Small tyre pump (not mini)
1 Co2 pump
Zip ties
spare keys for house, bike locks
Phone
Pen and paper
10 sheets of kitchen roll
Very small bottle of hand cleaner
Insulation tape
£5 in small change
Small roll of gaffer tape
Brake and gear cables
Spare bite valve for camalbac
Small roll string
Spare gloves