Confirm this is a Node library issue and not an underlying OpenAI API issue

• This is an issue with the Node library

Describe the bug

The service_tier should accept "priority" (per the API docs), but the type definition for ChatCompletionCreateParamsBase.service_tier only allows 'auto' | 'default' | 'flex' | 'scale' | null.
As a result, passing "priority" causes a TypeScript error and forces a type-cast workaround.

To Reproduce

1. Install latest openai (npm i openai@<version>) in a TypeScript project.

2. Add the code below and run tsc (or your IDE’s type-checker):

   import { OpenAI } from 'openai';
   const openai = new OpenAI({ ... });
   
   await openai.chat.completions.create({
     model: "gpt-4.1",
     messages: [{ role: "user", content: "Hello" }],
     service_tier: "priority", // should be accepted
   });

3. Observe the compiler error:

No overload matches this call.
  Overload 1 of 3, '(body: ChatCompletionCreateParamsNonStreaming, options?: RequestOptions | undefined): APIPromise<ChatCompletion>', gave the following error.
    ...
      Types of property 'service_tier' are incompatible.
        Type '"priority" | undefined' is not assignable to type '"default" | "auto" | "flex" | "scale" | null | undefined'.

Code snippets

/**
 * Specifies the latency tier to use for processing the request.
 */
service_tier?: 'auto' | 'default' | 'flex' | 'scale' | null;

OS

All

Node version

Node v22.11.0

Library version

openai v5.7.0