Under Lifting and Carrying (PHB 176) it says:
Your carrying capacity is your Strength score multiplied by 15. This is the weight (in pounds) that you can carry… You can push, drag, or lift a weight in pounds up to twice your carrying capacity (or 30 times your Strength score).
and also specifies that a tiny creature can carry half as much
A sprite familiar summoned through a warlock’s Pact of Chain feature has a strength score of 3 and so has a carrying capacity of 22.5 pounds and a push, drag, lift limit of 45 pounds. The sprite stat block also specifies, however, that they wear leather armor and carry a longsword and shortbow.
Supposedly these weigh 10 pounds, 3 pounds and 2 pounds respectively but considering they are smaller than those worn by a medium humanoid it is unlikely that they weigh as much.
Is there any official guidance as to how much the sprite familiar’s equipment counts against its carrying capacity?