It very well may be just from drinking a lot, it's common in the summer when they are trying to cool themselves. Behavior is just as important to observe, and changes, being lethargic or not eating or drinking well, or weight loss would be concerning. It isn't a bad idea to get a fecal done once or twice a year to check for parasites, just to be sure. If you have a vet that will do it that's awesome, if not you can use mail in options.
https://www.amazon.com/dp/B000J5SOZ4/?tag=backy-20
Earth worms can be a vector for tapeworm, many other worms/parasites are commonly picked up from the soil directly. But eating earth worms doesn't mean that for sure it's an issue, if there is little or no worm load in your environment then the earth worms may not be carrying anything. A fecal will answer that for you. Tapeworm or roundworm are
sometimes seen in droppings, but not always. Most worms live the entire life cycle inside the bird, the fecal checks for eggs which are microscopic.
https://www.backyardchickens.com/articles/internal-parasites-parasitic-worms-in-chickens.66969/