## What this section solves

It defines how to build predictable integrations in a `webhook-first` model, reducing drift between temporary and final states.

## Contract principles

- Mutating requests must use idempotency.
- Events are the final source of operational truth.
- Versioning and naming must be explicit per domain.

## Recommended path

<Steps>
  <Step title="1) Read baseline contracts">Start with [API essentials](/docs/apis-events/api-essentials).</Step>
  <Step title="2) Define event semantics">Apply [Event conventions](/docs/apis-events/event-conventions).</Step>
  <Step title="3) Close execution safety">Validate [Authentication and idempotency](/docs/apis-events/authentication-idempotency).</Step>
  <Step title="4) Capture architecture rationale">Document trade-offs in [Webhook-first architecture](/docs/apis-events/webhook-first-architecture).</Step>
</Steps>

## Integration quality criteria

| Criterion | Operational target |
| --- | --- |
| Duplicate processing | 0 duplicate side effects |
| Retry success | 100% with bounded backoff policy |
| Events without schema | 0 in production |
| Persistent 5xx errors | No backlog outside SLO window |