## Summary

LiteLLM's current ChatGPT OAuth support appears to be effectively single-account per proxy process because the authenticator only reads one global `CHATGPT_TOKEN_DIR` / `CHATGPT_AUTH_FILE` pair.

This makes it difficult to run multiple ChatGPT subscription accounts in a single LiteLLM instance, even when users want to expose them as separate model groups / aliases.

## What I tried

I deployed LiteLLM database/admin mode and attempted to configure two ChatGPT-backed model groups in one instance, conceptually like:

- `gpt1/*` -> ChatGPT account A - `gpt2/*` -> ChatGPT account B

At the container / config level, I mounted two auth directories, e.g.

- `/app/chatgpt-auth-gpt1` - `/app/chatgpt-auth-gpt2`

and defined separate model groups in `config.yaml`.

However, after inspecting the running container, the ChatGPT auth path still seems globally bound by env vars:

- `CHATGPT_TOKEN_DIR` - `CHATGPT_AUTH_FILE`

and the current implementation in `litellm/llms/chatgpt/authenticator.py` appears to initialize a single auth file path for the whole process.

## Why this is a problem

For operators using ChatGPT subscription auth as an upstream, there are practical cases where mu…