OpenAPI auto generated meta from defineEventHandler<{ body: {...} }> Request types

Describe the feature

I was looking for a way to auto generate openAPI meta based of my api routes.

defineEventHandler already allows to define the Request type like:

export default defineEventHandler<{
body: { foo: string, bar: boolean },
}>(() => {});

or something like:

import { z } from 'zod';
const bodySchema = z.object({
foo: z.string(),
bar: z.boolean(),
});
export default defineEventHandler<{
body: z.infer<typeof bodySchema>,
}>(() => {});

I came across this issue: #2974
But it would be nice, to be able to define it with defineEventHandler.

Thanks!

Additional information

• Would you be willing to help implement this feature?

Start by reading the defineEventHandler request-type examples in this issue and the referenced issue #2974. Determine how OpenAPI metadata could be derived for both explicit TypeScript request types and zod-inferred types. Done means the supported route definitions produce usable OpenAPI request metadata, but the implementation scope and validation approach are not specified here.