Technically, all fruits and vegetables are carbs. They're just a carb that happens to be high in fat. Semantics.
Here's some nutrition facts about avocados:
Avocado Nutrition Facts – Superfoods! Avocado Nutrition Facts
Sure, they're relatively high in carbs, but it's practically all fiber.
This is what I love:
Glycemic Index GI Avocado
Glycemic Index & Avocados | LIVESTRONG.COM
Fruits in general rank low on the glycemic index. There are some exceptions; the watermelon is the highest common fruit with a high-GI rank of 80. Avocados are classified as a fruit although they are often thought of as a vegetable, as typically they are eaten with savory meals. The GI is relevant only for carbohydrate foods, and as avocados have a very low-carb content, they are assigned a zero on the glycemic index.