Foundry Toolkit model catalog fails to load models after repeated /foundry/list calls trigger 429 TooManyRequests

Summary

Foundry Toolkit for VS Code is unable to show models in the model catalog. Prompt/agent discovery works, but model discovery repeatedly hits 429 TooManyRequests / QuotaExceeded from both Azure Foundry catalog and GitHub model catalog APIs.

Environment

• Product: Foundry Toolkit for VS Code
• Extension version: 1.4.2
• VS Code: VS Code Insiders
• OS: Windows
• Local service: Inference.Service.Agent.exe
• Local API observed: http://localhost:5272/foundry/list
• Azure Foundry catalog region in error: eastus2

Reproduction Steps

1. Sign in to Azure from VS Code.
2. Open Foundry Toolkit.
3. Open or refresh the model catalog/model list.
4. Observe that models do not appear correctly.
5. Check Foundry Toolkit.log.

Expected Behavior

Foundry Toolkit should load the model catalog without repeatedly triggering throttling. If a catalog request is throttled, it should honor Retry-After, back off, and avoid duplicate concurrent refreshes.

Actual Behavior

Foundry Toolkit repeatedly calls the local /foundry/list endpoint, which then attempts to fetch model catalog data. The catalog calls are throttled with 429 TooManyRequests / QuotaExceeded, and models are not shown correctly.

Prompt/agent discovery appears to work, but model catalog discovery fails.

Error Details

Observed repeated errors in Foundry Toolkit.log:

Exception fetching models from Azure Foundry catalog
System.Exception: Failed: Fetching model list from Foundry Catalog
---> System.Net.Http.HttpRequestException: Received too many requests in a short amount of time. Retry again after 1 seconds.

"statusCode": 429
"code": "UserError"
"message": "Received too many requests in a short amount of time. Retry again after 1 seconds."
"innerError": {
  "code": "QuotaExceeded",
  "innerError": {
    "code": "TooManyRequests"
  }
}