Standard Schema

Standard Schema is a common standard for validation libraries. It is supported by tRPC, Hono, TanStack Form, React Hook Form, Nuxt UI and others. Every tinyval schema implements it, so you can pass schemas to these libraries directly — no adapters needed.

How it works

Every schema has a ~standard property with a validate method and input/output types:

const result = User['~standard'].validate(input);
// { value: { ... } } or { issues: [{ message: 'Invalid email', path: ['email'] }] }

• If the schema contains checkAsync, validate returns a Promise.
• Error messages are the same as in validate, including setMessages.
• Custom schemas created with createSchema support the standard too.

Examples

tRPC

export const appRouter = t.router({
  createUser: t.procedure.input(CreateUser).mutation(({ input }) => db.users.create(input)),
});

Hono

import { sValidator } from '@hono/standard-validator';

app.post('/users', sValidator('json', CreateUser), (c) => {
  const user = c.req.valid('json'); // typed
  return c.json(user, 201);
});

TanStack Form

const form = useForm({
  defaultValues: { name: '', email: '' },
  validators: { onChange: CreateUser },
});

React Hook Form

import { standardSchemaResolver } from '@hookform/resolvers/standard-schema';

const form = useForm({ resolver: standardSchemaResolver(CreateUser) });

See also

• createSchema — custom schemas with standard support
• TypeScript