# API [#api]

Use this section when your caller needs HTTP transport, generated endpoint
contracts or OpenAPI reference material.

## Pages [#pages]

* [Overview](/api/overview)
* [Authentication and deployment assumptions](/api/authentication-and-deployment-assumptions)
* [Errors](/api/errors)
* [OpenAPI reference](/api/openapi-reference)
* [Endpoints](/api/endpoints)
* [Agent connection guide](/api/agent-tools)

## Runtime graph [#runtime-graph]

```ts
Production: HTTP calculate

HTTP caller
  -> @taxkit/api-http route contract
    -> CalculatorApiHandlerLive
      -> PublicCalculatorService.calculate
        -> CalculationEngine
```

## Related sections [#related-sections]

* [SDK](/sdk)
* [Guides](/guides)
* [Reference](/reference)