What is Enterprise Subregistry?

The public MCP Registry at registry.mcphub.io enables global discovery of open-source MCP servers, but enterprises cannot publish proprietary tools there, exposing internal capabilities to the public internet is an obvious security violation. The Enterprise Subregistry solves this by implementing the same OpenAPI discovery specification behind the corporate firewall. It functions as an internal app store for AI capabilities. Each MCP server registered in the subregistry includes metadata (description, version, owner, classification level), access control rules (which teams/agents can discover and invoke it), and usage quotas (rate limits, cost allocation codes). The registry itself runs as a lightweight service (typically a Next.js API route backed by PostgreSQL) that exposes a standard /v1/servers endpoint for agent discovery. When an internal AI agent needs to accomplish a task, it queries the subregistry to discover available tools, authenticates via OAuth 2.1 with scoped tokens, and invokes the appropriate MCP server. All interactions are logged to an immutable audit trail for SOC2/HIPAA compliance. The architecture supports federation, multiple subregistries across business units can selectively share capabilities through cross-registry trust relationships.