Azure managed identity with BYOK

This guide shows how to use DefaultAzureCredential from the Azure Identity library to authenticate with Azure AI Foundry models through the Copilot SDK.

How it works

Azure AI Foundry's OpenAI-compatible endpoint accepts bearer tokens from Entra ID in place of static API keys. The pattern is:

Use DefaultAzureCredential to obtain a token for the https://cognitiveservices.azure.com/.default scope
Pass the token as the bearer_token in the BYOK provider config
Refresh the token before it expires (tokens are typically valid for ~1 hour)

Diagram: Sequence diagram showing the described process.

Python example

Prerequisites

pip install github-copilot-sdk azure-identity

Basic usage

import asyncio
import os

from azure.identity import DefaultAzureCredential
from copilot import CopilotClient
from copilot.session import PermissionHandler, ProviderConfig

COGNITIVE_SERVICES_SCOPE = "https://cognitiveservices.azure.com/.default"

async def main():
    # Get a token using Managed Identity, Azure CLI, or other credential chain
    credential = DefaultAzureCredential()
    token = credential.get_token(COGNITIVE_SERVICES_SCOPE).token

    foundry_url = os.environ["AZURE_AI_FOUNDRY_RESOURCE_URL"]

    client = CopilotClient()
    await client.start()

    session = await client.create_session(
        on_permission_request=PermissionHandler.approve_all,
        model="gpt-4.1",
        provider=ProviderConfig(
            type="openai",
            base_url=f"{foundry_url.rstrip('/')}/openai/v1/",
            bearer_token=token,  # Short-lived bearer token
            wire_api="responses",
        ),
    )

    response = await session.send_and_wait("Hello from Managed Identity!")
    print(response.data.content)

    await client.stop()

asyncio.run(main())

Token refresh for long-running applications

Bearer tokens expire (typically after ~1 hour). For servers or long-running agents, refresh the token before creating each session:

from azure.identity import DefaultAzureCredential
from copilot import CopilotClient
from copilot.session import PermissionHandler, ProviderConfig

COGNITIVE_SERVICES_SCOPE = "https://cognitiveservices.azure.com/.default"

class ManagedIdentityCopilotAgent:
    """Copilot agent that refreshes Entra ID tokens for Azure AI Foundry."""

    def __init__(self, foundry_url: str, model: str = "gpt-4.1"):
        self.foundry_url = foundry_url.rstrip("/")
        self.model = model
        self.credential = DefaultAzureCredential()
        self.client = CopilotClient()

    def _get_provider_config(self) -> ProviderConfig:
        """Build a ProviderConfig with a fresh bearer token."""
        token = self.credential.get_token(COGNITIVE_SERVICES_SCOPE).token
        return ProviderConfig(
            type="openai",
            base_url=f"{self.foundry_url}/openai/v1/",
            bearer_token=token,
            wire_api="responses",
        )

    async def chat(self, prompt: str) -> str:
        """Send a prompt and return the response text."""
        # Fresh token for each session
        session = await self.client.create_session(
            on_permission_request=PermissionHandler.approve_all,
            model=self.model,
            provider=self._get_provider_config(),
        )

        response = await session.send_and_wait(prompt)
        await session.disconnect()

        return response.data.content if response else ""

Node.js / TypeScript example

import { DefaultAzureCredential } from "@azure/identity";
import { CopilotClient } from "@github/copilot-sdk";

const credential = new DefaultAzureCredential();
const tokenResponse = await credential.getToken(
  "https://cognitiveservices.azure.com/.default"
);

const client = new CopilotClient();

const session = await client.createSession({
  model: "gpt-4.1",
  provider: {
    type: "openai",
    baseUrl: `${process.env.AZURE_AI_FOUNDRY_RESOURCE_URL}/openai/v1/`,
    bearerToken: tokenResponse.token,
    wireApi: "responses",
  },
});

const response = await session.sendAndWait({ prompt: "Hello!" });
console.log(response?.data.content);

await client.stop();

.NET example

using Azure.Identity;
using GitHub.Copilot;

var credential = new DefaultAzureCredential();
var token = await credential.GetTokenAsync(
    new Azure.Core.TokenRequestContext(
        new[] { "https://cognitiveservices.azure.com/.default" }));

await using var client = new CopilotClient();
var foundryUrl = Environment.GetEnvironmentVariable("AZURE_AI_FOUNDRY_RESOURCE_URL");

await using var session = await client.CreateSessionAsync(new SessionConfig
{
    Model = "gpt-4.1",
    Provider = new ProviderConfig
    {
        Type = "openai",
        BaseUrl = $"{foundryUrl!.TrimEnd('/')}/openai/v1/",
        BearerToken = token.Token,
        WireApi = "responses",
    },
});

var response = await session.SendAndWaitAsync(
    new MessageOptions { Prompt = "Hello from Managed Identity!" });
Console.WriteLine(response?.Data.Content);

Environment configuration

Variable	Description	Example
`AZURE_AI_FOUNDRY_RESOURCE_URL`	Your Azure AI Foundry resource URL	`https://myresource.openai.azure.com`

No API key environment variable is needed—authentication is handled by DefaultAzureCredential, which automatically supports:

Managed Identity (system-assigned or user-assigned): for Azure-hosted apps
Azure CLI (az login): for local development
Environment variables (AZURE_CLIENT_ID, AZURE_TENANT_ID, AZURE_CLIENT_SECRET): for service principals
Workload Identity: for Kubernetes

See the DefaultAzureCredential documentation for the full credential chain.

When to use this pattern

Scenario	Recommendation
Azure-hosted app with Managed Identity	✅ Use this pattern
App with existing Azure AD service principal	✅ Use this pattern
Local development with `az login`	✅ Use this pattern
Non-Azure environment with static API key	Use BYOK (bring your own key)
GitHub Copilot subscription available	Use GitHub OAuth setup

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