---

This section details on the original issue you should resolve

<issue_title>Codegen outputs invalid ‎_heyapi_xxx_ identifiers after 0.86 and type‑only imports regressed</issue_title>
<issue_description>### Description

Since version 0.86, generated code appears incorrect and references non‑existent internal identifiers. I’m not aware of any breaking changes that would explain this behavior.
Here is a representative example from a freshly generated file:

// This file is auto-generated by @hey-api/openapi-ts

export const zErrorResponseDto = _heyapi_671_.object({
  success: _heyapi_671_.boolean(),
  message: _heyapi_671_.string(),
  errorCode: _heyapi_671_.number(),
  error: _heyapi_671_.string(),
  timestamp: _heyapi_671_.string(),
});

In the generated output, many ‎_heyapi_xxx_ symbols (e.g., ‎_heyapi_671_) do not exist or are not imported from anywhere, causing compile-time failures.

Additionally, enabling verbatimModuleSyntax would require the generator to emit ‎import { type ClientOptions } instead of ‎import { ClientOptions }. If the codegen ignores this constraint, TypeScript will error

• In 0.85.x (correct): import { type ClientOptions, type Config, createClient, createConfig } from "./client";

• In 0.86.x (regressed): import { ClientOptions, Config, createClient, createConfig } from "./client";

Reproducible example or configuration

Switch between 0.85.2 and 0.86.x to compare the output differences.

// openapi-ts.config.ts
import path from "node:path";

import { defineConfig } from "@hey-api/openapi-ts";

export default defineConfig({
  input: `https://gist.githubusercontent.com/nghiepdev/b2c9996750505ec82adb04fdc9b95ea6/raw/ebe990458001a5c4d3e1de0218f93dcb8f132db8/test-openapi.json`,
  output: {
    format: "prettier",
    lint: null,
    path: "generated/client",
  },
  plugins: [
    {
      name: "@hey-api/transformers",
    },
    {
      name: "@hey-api/client-next",
      runtimeConfigPath: path.resolve(process.cwd(), "./generated/hey-api.ts"),
      throwOnError: false,
    },
    {
      name: "@tanstack/react-query",
    },
    {
      name: "zod",
    },
    {
      name: "@hey-api/sdk",
      validator: true,
      transformer: true,
    },
  ],
});

OpenAPI specification (optional)

https://gist.githubusercontent.com/nghiepdev/b2c9996750505ec82adb04fdc9b95ea6/raw/ebe990458001a5c4d3e1de0218f93dcb8f132db8/test-openapi.json

System information (optional)

@hey-api/openapi-ts@0.86.x</issue_description>

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