Prefix every generated type name

Set resolver.name to patch the casing rule plugin-ts uses for every symbol. This override prefixes each generated type with Api, so generated names never collide with hand-written types of the same domain concept.

kubb.config.ts

import { defineConfig } from 'kubb/config'
import { pluginTs } from '@kubb/plugin-ts'

export default defineConfig({
  input: './petStore.yaml',
  output: { path: './src/gen', clean: true },
  plugins: [
    pluginTs({
      resolver: {
        name(name) {
          return `Api${name}`
        },
      },
    }),
  ],
})

Output example

src/gen/types/Pet.ts

import type { ApiCat } from './Cat'
import type { ApiCategory } from './Category'
import type { ApiDog } from './Dog'
import type { ApiTag } from './Tag'

export type ApiPet = (((ApiDog & {
    readonly type: "dog";
}) | (ApiCat & {
    readonly type: "cat";
})) & {
    id?: bigint;
    name: string;
    category?: ApiCategory;
});

usage.ts

import type { ApiPet } from './src/gen/types/Pet'

function describe(pet: ApiPet) {
  return pet.name
}

TIP

The name callback receives the type name already cased, so returning `Api${name}` is enough. The general resolver guide shows this same pattern wrapped in this.default.name(name), reusing the built-in casing, but that call re-lowercases the first letter instead (ApiCat becomes Apicat), so this recipe skips it and prefixes the incoming name directly.