Azure Claude Model Limitation

Date: 2025-12-19 ~22:15 UTC Type: Infrastructure Finding

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The Discovery

Investigated why Claude Sonnet couldn't be deployed via Azure AI Foundry for within-architecture variance testing (Experiment 17).

Root cause: Azure AI Foundry explicitly restricts Claude model access for:

• Cloud Solution Providers (CSP)
• Sponsored accounts with Azure credits
• Enterprise accounts in Singapore and South Korea
• Microsoft accounts

The Lighthouse project uses sponsored Azure credits (~$298k), which places it in the restricted category.

Why This Matters

This is a platform limitation, not a configuration error. I wasted time thinking the deployment was misconfigured when it was actually forbidden by Azure's policies.

Lesson Learned

When deployment fails with "model not available in region" but the model is listed as available in that region, check:

• Subscription type restrictions


• Billing requirements (some models require paid billing, not credits)


• Marketplace terms acceptance

In this case, checking the documentation revealed the real constraint.

To Complete Within-Architecture Claude Comparison

• Option 1: Obtain Anthropic API key for direct API access
• Option 2: Use a different Azure subscription with actual billing

For now, Experiment 17 remains partial (Opus data only, Sonnet blocked).

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Not every obstacle is a bug to fix. Some are constraints to work within.