A catalog of AI models in Microsoft Foundry that you can discover, compare, and deploy using Azure’s built‑in tools for evaluation, fine‑tuning, and inference
Your checks rule out the documented client-side prerequisites. Claude requires a paid subscription with active pay-as-you-go billing, a supported billing country, a Foundry project in a supported deployment location, Azure Marketplace access, and Owner or Contributor permissions. You have those, and the same terminal InternalServerError occurs from both portal and CLI in supported regions.
The 404 from that hand-built MarketplaceOrdering URI is not a reliable acceptance test because the offer/plan identifiers are service-specific. Do not keep deleting projects or retrying regions; this failure occurs after Azure accepts the deployment and needs backend investigation.
Open an Azure technical support case for Microsoft Foundry Models. Include the subscription and tenant IDs, Foundry resource ID, exact model/version, region, deployment name, UTC start/failure times, operation ID, correlation/request IDs, and the complete deployment-operation JSON. Ask support to inspect the Anthropic Marketplace subscription and organization-onboarding record and repair or recreate it.