The core kit
Water, a collapsible bowl, leash, waste bags, and any event-required documentation are a practical baseline. Check the organizer's current requirements before adding anything more.
Comfort beats overpacking
A familiar treat, cooling option, shade plan, and quiet reset can be more useful than a large bag of extras. Choose the smallest kit that lets you respond well to your dog.
Leave room for the actual rules
Some places publish restrictions on leash length, crowd access, food areas, and weather operations. The current official event page always wins over a generic packing list.