microsoft/semantic-kernel · error · InvalidOperationException

AZURE_OPENAI_ENDPOINT is not set.

Error message

AZURE_OPENAI_ENDPOINT is not set.

What it means

The Azure OpenAI Responses ToolCall migration sample throws InvalidOperationException when AZURE_OPENAI_ENDPOINT is null. This sample demonstrates function calling (GetWeather) through the OpenAI Responses API on Azure OpenAI, comparing SK's OpenAIResponseAgent with the Agent Framework. The endpoint backs the Responses API client.

Source

Thrown at dotnet/samples/AgentFrameworkMigration/AzureOpenAIResponses/Step03_ToolCall/Program.cs:14

// Copyright (c) Microsoft. All rights reserved.

using System.ComponentModel;
using Azure.AI.OpenAI;
using Azure.Identity;
using Microsoft.Extensions.AI;
using Microsoft.SemanticKernel;
using Microsoft.SemanticKernel.Agents.OpenAI;
using OpenAI.Responses;

#pragma warning disable OPENAI001 // Type is for evaluation purposes only and is subject to change or removal in future updates. Suppress this diagnostic to proceed.
#pragma warning disable SKEXP0110 // Type is for evaluation purposes only and is subject to change or removal in future updates. Suppress this diagnostic to proceed.

var endpoint = Environment.GetEnvironmentVariable("AZURE_OPENAI_ENDPOINT") ?? throw new InvalidOperationException("AZURE_OPENAI_ENDPOINT is not set.");
var deploymentName = System.Environment.GetEnvironmentVariable("AZURE_OPENAI_DEPLOYMENT_NAME") ?? "gpt-4o";
var userInput = "What is the weather like in Amsterdam?";

Console.WriteLine($"User Input: {userInput}");

[KernelFunction]
[Description("Get the weather for a given location.")]
static string GetWeather([Description("The location to get the weather for.")] string location)
    => $"The weather in {location} is cloudy with a high of 15°C.";

await SKAgentAsync();
await SKAgent_As_AFAgentAsync();
await AFAgentAsync();

async Task SKAgentAsync()
{
    OpenAIResponseAgent agent = new(new AzureOpenAIClient(new Uri(endpoint), new AzureCliCredential())
        .GetResponsesClient(), deploymentName)

View on GitHub (pinned to c028a0c7dc)

Solutions

1. Set AZURE_OPENAI_ENDPOINT to your Azure OpenAI resource URL
2. Optionally set AZURE_OPENAI_DEPLOYMENT_NAME (defaults to gpt-4o)
3. Ensure the deployed model supports function calling via the Responses API
4. Run az login for AzureCliCredential

Example fix

// before
var endpoint = Environment.GetEnvironmentVariable("AZURE_OPENAI_ENDPOINT") ?? throw new InvalidOperationException("AZURE_OPENAI_ENDPOINT is not set.");

// after
var endpoint = Environment.GetEnvironmentVariable("AZURE_OPENAI_ENDPOINT");
if (string.IsNullOrWhiteSpace(endpoint))
    throw new InvalidOperationException(
        "AZURE_OPENAI_ENDPOINT is not set. Responses API tool-calling requires it.");

var endpoint = Environment.GetEnvironmentVariable("AZURE_OPENAI_ENDPOINT");
if (string.IsNullOrWhiteSpace(endpoint))
{
    Console.Error.WriteLine("AZURE_OPENAI_ENDPOINT is not set. Required for Responses API tool-calling.");
    return;
}

static bool IsAzureOpenAIEndpointConfigured() =>
    !string.IsNullOrWhiteSpace(Environment.GetEnvironmentVariable("AZURE_OPENAI_ENDPOINT"));

try
{
    var endpoint = Environment.GetEnvironmentVariable("AZURE_OPENAI_ENDPOINT")
        ?? throw new InvalidOperationException("AZURE_OPENAI_ENDPOINT is not set.");
}
catch (InvalidOperationException ex) when (ex.Message.Contains("AZURE_OPENAI_ENDPOINT"))
{
    Console.Error.WriteLine(ex.Message);
    return;
}

When it happens

Trigger: Running AzureOpenAIResponses/Step03_ToolCall without AZURE_OPENAI_ENDPOINT. The throw at line 14 fires before the GetWeather KernelFunction is registered.

Common situations: Using the chat-completion ToolCall sample env vars (same variable name but different default deployment); the Responses API may not support all function-calling features available in chat completions; az login expired.

Related errors

• AZURE_OPENAI_ENDPOINT is not set.
• AZURE_OPENAI_ENDPOINT is not set.
• AZURE_OPENAI_ENDPOINT is not set.
• AZURE_OPENAI_ENDPOINT is not set.
• AZURE_OPENAI_ENDPOINT is not set.

AI-assisted analysis of microsoft/semantic-kernel@c028a0c7dc (2026-08-13). Data as JSON: /api/errors/007902a0b64ade5a. Report an issue: GitHub.