Posit Assistant / Microsoft Foundry authentication using Entra ID?

[deschwartz]

Is there currently a supported way for local Posit Assistant (in either RStudio Desktop or Positron) to authenticate to Microsoft Foundry using Entra ID/Azure CLI credentials rather than an API key? I can successfully authenticate to our Foundry deployment from Python using DefaultAzureCredential() after az login, but our organization disables API-key authentication.

[jonvanausdeln]

@deschwartz , Thank you for reaching out!

Currently, the only for Foundry authentication in Positron desktop is via an API key. Posit Workbench also allows authentication via their managed credentials feature, but sounds like you are only on desktop.

For Rstudio, you could add your comments to posit-dev/assistant-feedback#85.

And feel free to log a Positron issue of what you'd like.

[deschwartz]

Thanks for the quick reply!

I actually ended up getting Posit Assistant working in RStudio. My organization put an API Management gateway in front of Foundry that exposes an OpenAI-compatible /chat/completions endpoint and authenticates with an Ocp-Apim-Subscription-Key header. I configured that as a custom OpenAI-compatible provider, manually specified the deployed model, and chat/tools seem to be working normally.

I also tried the same setup in Positron, and it now recognizes the custom model from providers.json, but when I try to use it I get:

No credentials available for provider: openai-compatible

The Custom Provider UI still seems to require a conventional API key even though authentication for this endpoint is entirely through the custom header. This looks related to #15248. Is that the expected limitation for now, or is there another supported way to use a custom-header-only credential in Positron?

Also, is there a recommended way to supply the Ocp-Apim-Subscription-Key without storing it directly in ~/.posit/ai/providers.json—for example with an environment variable or credential store?

I’ll still add my support to the Entra ID feature request, since native Entra authentication on desktop would be cleaner.

[jonvanausdeln]

I'm glad you could get the RStudio version working for you. Unfortunately, for Positron I think you'll have to wait for #15248 to get what you'd like.