API ReferencePublic APICreate a subscription plan for a productCreate a subscription plan for a product POST /v1/products/:productId/plans Create a subscription plan for a product Request Responses201400401403409422Plan createdValidation errorAuthentication failedInsufficient permissionIdempotency or state conflictValidation errorDid this page unblock the next step?ResolvedNeeds improvementFeedback stays inside the docs flow and should never include customer or card data.