skills/vibe-payments/references/payments-webhook-reconciliation-check.md

# Payments Webhook & Reconciliation Check

## Operation

Verify the selected invariant through bounded scenarios in an authorized environment. Do not turn verification into unrelated implementation. Return passed, failed or blocked, with actual evidence and any missing required scenario.

## Goal

Verify one payment webhook, state transition, or reconciliation invariant through safe duplicate, delayed, failed, and out-of-order scenarios.

## Required input

Provide provider, selected event/state transition, implementation summary or patch boundary, expected local state/entitlement result, safe sandbox/mock environment, fixture events, and repository-native commands.

## Scenarios

- Verify webhook signature/authentication and rejection of invalid events.
- Replay the same event and prove idempotent local state and side effects.
- Deliver delayed or out-of-order events and verify legal state transitions.
- Exercise provider failure, local transaction failure, retry/reconciliation, and entitlement consistency.
- Confirm user-visible billing/API state and audit/notification behavior when directly affected.