Porridge stretches a little rice a long way. A 350g bowl of arroz caldo has only about 60g of dry rice in it, cooked in 5 times its weight of broth, so the rice contributes about 200 calories. That is less than a cup of plain rice. The chicken piece, usually a thigh or a chunk of breast with skin, adds 100 to 150. Kawaling Pinoy's recipe card lands at 572 per serving because it splits a whole chicken 6 ways, which is a much bigger piece than a carinderia gives you.
The toppings are where the oil hides. Toasted garlic is fried in oil and spooned on with some of that oil, about 45 calories. Some places also drizzle chicken fat or use the annatto oil from inasal, which adds 60 more. A whole boiled egg instead of half is another 35. A fully loaded bowl with a big thigh, whole egg and extra oil is about 550 calories, still a reasonable meal.
The calamansi and patis are free, so use them. A bowl costs 50 to 70 pesos at a carinderia and 90 to 130 at a Goto King or a mall stall, and the mall versions come with more chicken and often a side of tokwa't baboy, which is another 250. As comfort food goes, arroz caldo is one of the better deals: warm, filling, about 20g of protein and under 400 calories if you keep it simple.