litellm - 💡(How to fix) Fix [Bug]: Test ChatGPT in ui dashboard [1 participants]

image:
      repository: ghcr.io/berriai/litellm-database
      tag: "v1.85.0-rc.1"

[...]

    proxy_config:
      model_list:
        - model_name: chatgpt/gpt-5.5
          model_info:
            mode: responses
          litellm_params:
            model: chatgpt/gpt-5.5
      general_settings:

---

{
    "status": "error",
    "result": {
        "use_in_pass_through": false,
        "use_litellm_proxy": false,
        "merge_reasoning_content_in_choices": false,
        "model": "chatgpt/gpt-5.5",
        "max_tokens": 5,
        "cache": {
            "no-cache": true
        },
        "error": "litellm.BadRequestError: ChatgptException - {\"detail\":\"Input must be a list\"}\nstack trace: Traceback (most recent call last):\n File \"/app/.venv/lib/python3.13/site-packages/litellm/llms/custom_httpx/llm_http_handler.py\", line 2461, in async_response_api_handler\n response = await async_httpx_client.post(\n ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n ...<5 lines>...\n )\n ^\n File \"/app/.venv/lib/python3.13/site-packages/litellm/litellm_core_utils/logging_utils.py\", line 297, in async_wrapper\n result = await func(*args, **kwargs)\n ^^^^^^^^^^^^^^^^^^^^^^^^^^^\n File \"/app/.venv/lib/python3.13/site-packages/litellm/llms/custom_httpx/http_handler.py\", line 672, in post\n await _raise_masked_async_error(e, stream)\n File \"/app/.venv/lib/python3.13/site-packages/litellm/llms/custom_httpx/http_handler.py\", line 461, in _raise_masked_async_error\n raise MaskedHTTPStatusError(e, message=_text, text=_text) from None\nlitellm.llms.custom_httpx.http_handler.MaskedHTTPStatusError: Client error '400 Bad Request' for url 'https://chatgpt.com/backend-api/codex/r",
        "raw_request_typed_dict": {
            "raw_request_api_base": "https://chatgpt.com/backend-api/codex/responses",
            "raw_request_body": {
                "model": "gpt-5.5",
                "input": "test from litellm",
                "instructions": "<truncated>",
                "store": false,
                "stream": true,
                "include": [
                    "reasoning.encrypted_content"
                ]
            },
            "raw_request_headers": {
                "Authorization": "Be****AQ",
                "content-type": "application/json",
                "accept": "text/event-stream",
                "originator": "codex_cli_rs",
                "user-agent": "codex_cli_rs/1.85.0 (Linux 5.15.0-176-generic; x86_64) unknown",
                "session_id": "<truncated>",
                "ChatGPT-Account-Id": "<truncated>"
            },
            "error": null
        }
    }
}

---