billing-automation

# Billing Automation Master automated billing systems including recurring billing, invoice generation, dunning management, proration, and tax calculation. ## Use this skill when - Implementing SaaS subscription billing - Automating invoice generation and delivery - Managing failed payment recovery (dunning) - Calculating prorated charges for plan changes - Handling sales tax, VAT, and GST - Processing usage-based billing - Managing billing cycles and renewals ## Do not use this skill when - You only need a one-off invoice or manual billing - The task is unrelated to billing or subscriptions - You cannot change pricing, plans, or billing flows ## Instructions - Define plans, pricing, billing intervals, and proration rules. - Map subscription lifecycle states and renewal/cancellation behavior. - Implement invoicing, payments, retries, and dunning workflows. - Model taxes and compliance requirements per region. - Validate with sandbox payments and reconcile ledger outputs. - If detailed templates are required, open `resources/implementation-playbook.md`. ## Safety - Do not charge real customers in testing environments. - Verify tax handling and compliance obligations before production rollout. ## Resources - `resources/implementation-playbook.md` for detailed patterns, checklists, and examples.