App integration

Add SolvaPay paywalls, usage, webhooks and billing UI to an existing TypeScript / JavaScript app or API.

Guardrails

Never expose SOLVAPAY_SECRET_KEY to client code or public env vars.
Never build custom card collection if hosted checkout satisfies requirements.
Always prefer official SolvaPay SDK helpers over ad-hoc raw HTTP calls.
Always confirm product and plan references exist before wiring UI.
Always keep paywall checks server-side or tool-handler-side.
Always emit a runnable sandbox verification artifact before handoff — a curl block or test script covering happy path (200) and failure path (402 with checkoutUrl). Prose summaries alone do not satisfy this guardrail.
Never treat UI unlock state as authoritative without server-side checks.