openai/openai-python · critical · ValueError

Must provide one of the `base_url` or `azure_endpoint` argum

Error message

Must provide one of the `base_url` or `azure_endpoint` arguments, or the `AZURE_OPENAI_ENDPOINT` environment variable

What it means

The synchronous AzureOpenAI client requires a service endpoint to build request URLs. None was supplied via the base_url argument, the azure_endpoint argument, or the AZURE_OPENAI_ENDPOINT environment variable, so the client cannot determine where to send requests and raises ValueError during construction.

Source

Thrown at src/openai/lib/azure.py:324

        if api_version is None:
            api_version = os.environ.get("OPENAI_API_VERSION")

        if api_version is None:
            raise ValueError(
                "Must provide either the `api_version` argument or the `OPENAI_API_VERSION` environment variable"
            )

        if default_query is None:
            default_query = {"api-version": api_version}
        else:
            default_query = {**default_query, "api-version": api_version}

        if base_url is None:
            if azure_endpoint is None:
                azure_endpoint = os.environ.get("AZURE_OPENAI_ENDPOINT")

            if azure_endpoint is None:
                raise ValueError(
                    "Must provide one of the `base_url` or `azure_endpoint` arguments, or the `AZURE_OPENAI_ENDPOINT` environment variable"
                )

            if azure_deployment is not None:
                base_url = f"{azure_endpoint.rstrip('/')}/openai/deployments/{azure_deployment}"
            else:
                base_url = f"{azure_endpoint.rstrip('/')}/openai"
        else:
            if azure_endpoint is not None:
                raise ValueError("base_url and azure_endpoint are mutually exclusive")

        if api_key is None:
            # define a sentinel value to avoid any typing issues
            api_key = API_KEY_SENTINEL

        super().__init__(
            api_key=api_key,
            admin_api_key=admin_api_key,

View on GitHub (pinned to 9917c6e28e)

Solutions

1. Set AZURE_OPENAI_ENDPOINT (e.g. https://myresource.openai.azure.com) in the environment
2. Pass azure_endpoint="https://myresource.openai.azure.com" to AzureOpenAI(...)
3. Alternatively pass base_url directly if you use a full custom URL

Example fix

// before
client = AzureOpenAI(api_version="2024-02-01")
// after
client = AzureOpenAI(azure_endpoint="https://myresource.openai.azure.com", api_version="2024-02-01")

import os
if not (os.environ.get("AZURE_OPENAI_ENDPOINT") or MY_AZURE_ENDPOINT):
    raise RuntimeError("AZURE_OPENAI_ENDPOINT or azure_endpoint is required")

try:
    client = AzureOpenAI(api_version=V)
except ValueError as e:
    if "azure_endpoint" in str(e):
        raise ConfigError(str(e)) from e
    raise

When it happens

Trigger: Constructing AzureOpenAI() with no azure_endpoint/base_url and no AZURE_OPENAI_ENDPOINT env var set; CI shells or stripped env where the variable was expected but absent.

Common situations: Env var not exported in the active shell/venv, .env file not loaded, deploying to a new environment without copying Azure config, or confusing OpenAI's OPENAI_BASE_URL with AZURE_OPENAI_ENDPOINT.

Understand the failure class

Background: "X is required", "must be set", "cannot be empty": the missing-required-config error family, from Vertex AI project/location to WeChat keys — this error's family across 18 libraries.

Related errors

• base_url and azure_endpoint are mutually exclusive
• The webhook secret must either be set using the env var, OPE
• `provider` cannot be combined with top-level {formatted}. Mo
• The `api_key` and `workload_identity` arguments are mutually
• Missing credentials. Please pass an `api_key`, `workload_ide

AI-assisted analysis of openai/openai-python@9917c6e28e (2026-08-28). Data as JSON: /api/errors/98d2d06029a991ce. Report an issue: GitHub.