How can I set the client Id for a Function App without setting explicit authentication

Hello Parag Kale,

Thanks for reaching out, could you please confirm on the below?

• Did you want to configure the client ID in the environment variable and pass it to the function?

Yes , I want to set environment variables WEBSITE_AUTH_OPENID_ISSUER and WEBSITE_AUTH_CLIENT_ID for the function app , but not by setting easy auth in the portal under Authentication tab of the function app

Hello Parag Kale,

If you're leveraging the Graph library, you can configure Azure AD settings like ClientId in your Function App, add them as application settings using the format AzureAd__ClientId and AzureAd__TenantId (note the double underscores for nested keys). These will be available via IConfiguration in your code, e.g., _configuration["AzureAd:ClientId"] or _configuration.GetSection("AzureAd")["ClientId"]. If you're not leveraging MSAL, you can simply create ClientId application setting/environment variable and pull it in code using _configuration["ClientId"];. For local development, you can set the same keys in local.settings.json under the Values section. This approach keeps your configuration environment-specific, secure, and easy to manage.

I am working with azure app service and for one of the function app, I want to manually set above environment variables values without setting up easy auth at the function level

Hello Parag Kale,

Yes, you can manually set Azure AD-related environment variables like AzureAd__ClientId in your Function App's configuration without enabling EasyAuth, and access them in code via IConfiguration—they work independently for custom authentication flows.