The doctor visit does not bill for VSP, so you'll have to pay for it and get reimbursed by your insurance company. But the eyeglasses side does bill VSP for you!
You don't need to be a Costco member however, they do not accept/bill for VSP so you will need to pay out of pocket. You may be able to file the claim yourself with VSP but I'd check with them first about reimbursement.
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