The Hidden Reason Your Foundry Agent Can't Reach Any of Your Private (Bring-Your-Own) Resources

The setup You've built the deployment the enterprise architecture review asked for. Nothing touches the public internet. Your Microsoft Foundry resource is private — public network access disabled, a private endpoint fronting it inside your virtual network. Every resource the agent depends on is locked down the same way: Azure AI Search — private endpoint, public access off. Azure Storage — private endpoint, public access off. Azure Cosmos DB — private endpoint, public access off. An MCP server (say on Azure Functions, Container Apps or APIM) — private, reachable only from inside the VNet. You