Oh dear...
 

I noticed yesterday that the brake fluid in the reservoir for my front calipers was a little on the low side.

I then looked at the calipers, and it seems that the front left banjo bolt has been weeping oil down the caliper.

How should I proceed?

Nip up the bolt a bit, clean the caliper and refil/bleed the system as necessary?

Or

Strip down the caliper, clean the fluid off, get new washers, and refill and bleed the system from scratch?

I'd try nipping the bolt up & keeping a very close eye on things for a while.

Yeah - definitely try option 1 first and then if it's still doing it, then try the rebuild! :?

Nip up the caliper, see how yoou get on, if the feel of the lever is ok, then dont worry. If a little spongy, then just bleed as normal.