microsoft/autogen · error · InvalidOperationException

Please set environment variable AZURE_OPENAI_API_KEY

Error message

Please set environment variable AZURE_OPENAI_API_KEY

What it means

Guard in the Connect_To_Azure_OpenAI sample: it reads AZURE_OPENAI_API_KEY and throws InvalidOperationException when it is missing, because AzureOpenAIClient(new Uri(endpoint), new ApiKeyCredential(apiKey)) cannot authenticate without it. It is sample-authored fail-fast code executed before the OpenAIChatAgent is constructed; note this sample uses InvalidOperationException, unlike the Basic samples' plain Exception.

Source

Thrown at dotnet/samples/AgentChat/AutoGen.OpenAI.Sample/Connect_To_Azure_OpenAI.cs:18

// Copyright (c) Microsoft Corporation. All rights reserved.
// Connect_To_Azure_OpenAI.cs

#region using_statement
using System.ClientModel;
using AutoGen.Core;
using AutoGen.OpenAI.Extension;
using Azure.AI.OpenAI;
#endregion using_statement

namespace AutoGen.OpenAI.Sample;

public class Connect_To_Azure_OpenAI
{
    public static async Task RunAsync()
    {
        #region create_agent
        var apiKey = Environment.GetEnvironmentVariable("AZURE_OPENAI_API_KEY") ?? throw new InvalidOperationException("Please set environment variable AZURE_OPENAI_API_KEY");
        var endpoint = Environment.GetEnvironmentVariable("AZURE_OPENAI_ENDPOINT") ?? throw new InvalidOperationException("Please set environment variable AZURE_OPENAI_ENDPOINT");
        var model = Environment.GetEnvironmentVariable("AZURE_OPENAI_DEPLOY_NAME") ?? "gpt-4o-mini";

        // Use AzureOpenAIClient to connect to openai model deployed on azure.
        // The AzureOpenAIClient comes from Azure.AI.OpenAI package
        var openAIClient = new AzureOpenAIClient(new Uri(endpoint), new ApiKeyCredential(apiKey));

        var agent = new OpenAIChatAgent(
            chatClient: openAIClient.GetChatClient(model),
            name: "assistant",
            systemMessage: "You are a helpful assistant designed to output JSON.",
            seed: 0)
            .RegisterMessageConnector()
            .RegisterPrintMessage();
        #endregion create_agent

        #region send_message
        await agent.SendAsync("Can you write a piece of C# code to calculate 100th of fibonacci?");

View on GitHub (pinned to 027ecf0a37)

Solutions

1. Set AZURE_OPENAI_API_KEY from your Azure OpenAI resource (Portal -> Keys and Endpoint) in the launching environment.
2. Also set AZURE_OPENAI_ENDPOINT (required next line) and optionally AZURE_OPENAI_DEPLOY_NAME (defaults model to gpt-4o-mini).
3. Prefer IUserSecrets/CI secret variables over plain exports for long-lived setups.
4. Confirm you are not mixing SDK keys — this must be an Azure OpenAI resource key, not an sk- public key.

Example fix

// before
var apiKey = Environment.GetEnvironmentVariable("AZURE_OPENAI_API_KEY") ?? throw new InvalidOperationException("Please set environment variable AZURE_OPENAI_API_KEY");

// after
var apiKey = Environment.GetEnvironmentVariable("AZURE_OPENAI_API_KEY")
    ?? throw new InvalidOperationException("AZURE_OPENAI_API_KEY is not set. Copy a key from your Azure OpenAI resource and export it before running.");

var apiKey = Environment.GetEnvironmentVariable("AZURE_OPENAI_API_KEY");
var endpoint = Environment.GetEnvironmentVariable("AZURE_OPENAI_ENDPOINT");
if (string.IsNullOrWhiteSpace(apiKey) || string.IsNullOrWhiteSpace(endpoint))
{
    throw new InvalidOperationException("Both AZURE_OPENAI_API_KEY and AZURE_OPENAI_ENDPOINT are required.");
}

try
{
    await Connect_To_Azure_OpenAI.RunAsync();
}
catch (InvalidOperationException ex) when (ex.Message.Contains("AZURE_OPENAI_API_KEY"))
{
    Console.Error.WriteLine($"Missing Azure credential: {ex.Message}");
}

When it happens

Trigger: Calling Connect_To_Azure_OpenAI.RunAsync() with AZURE_OPENAI_API_KEY unset. The throw fires before AZURE_OPENAI_ENDPOINT is read, so an endpoint error cannot occur until the key is provided.

Common situations: Running OpenAI-sample suites with Azure credentials absent; key configured only for the public OpenAI endpoint; CI jobs without Azure secrets; fresh environment after cloning.

Related errors

• Please set AZURE_OPENAI_API_KEY environment variable.
• Please set AZURE_OPENAI_ENDPOINT environment variable.
• BING_API_KEY environment variable is not set
• Please set OPENAI_API_KEY environment variable.
• Please set OPENAI_API_KEY environment variable.

AI-assisted analysis of microsoft/autogen@027ecf0a37 (2026-08-15). Data as JSON: /api/errors/1b2ca3c80bb9ddf6. Report an issue: GitHub.