Horizon: The Secure MCP Gateway

MCP is spreading fast, and most teams are bolting servers onto their stack one at a time. Every new server is another set of credentials to manage, another surface to secure, another thing to audit. That sprawl gets dangerous quickly. Horizon collapses it into a single front door.

Every client connects to one place. Claude Desktop, Cursor, Codex, ChatGPT, your own AI agents. They authenticate once via SSO, OAuth, or API key, and Horizon brokers everything behind it. Authorization is enforced per tool with role-based scopes and policy, so a connected client only sees what its role allows. Credentials never leak to the client: Horizon holds and auto-refreshes each upstream OAuth token at the gateway, which means your clients never re-auth and your secrets never leave.

Behind the gateway, three kinds of surfaces. Custom servers you build in FastMCP and host on Horizon. External third-party connectors like Slack, GitHub, and Google Workspace, where Horizon manages each provider's OAuth for you. And Remix, where you mix and match upstreams into one curated surface and manage every authorization from a single screen.

Every request is logged, and attributable to a user session. This is the architecture that lets a regulated enterprise adopt MCP without handing the keys to every tool to every client. Built and run by the people who wrote FastMCP.

For the full picture, see the Horizon platform overview.