orpc-disabling-output-validation

name	oRPC Disabling Output Validation
description	Disable output validation for improved performance while keeping OpenAPI spec generation.
license	MIT
metadata	{"author":"Ali Torki","homepage":"https://github.com/ali-master","version":"1.0.0"}

Disabling Output Validation

By default, oRPC validates procedure outputs against their defined schemas. If you only define output schemas for OpenAPI specification generation, you can disable output validation to improve performance.

Configuration

Set initialOutputValidationIndex to NaN:

import { os } from '@orpc/server'

const base = os
  .$config({
    initialOutputValidationIndex: Number.NaN,
  })

All procedures built from base will have output validation disabled.

Limitation

This approach will not work if your schema transforms data into a different type during validation.

const procedure = base
  .output(z.object({ value: z.number().transform(val => String(val)) }))
  .handler(() => ({ value: 123 }))
  .callable()

const { value } = await procedure()

The client expects value as a string, but since validation is skipped, it receives a number.