OpenAI releases the Agents API in public beta on September 10, 2026, with built-in MCP server connections

OpenAI's API changelog recorded the Agents API entering public beta on September 10, 2026: "Released the Agents API in public beta. Build agents with a managed Codex harness while OpenAI handles session orchestration, context compaction, and recovery. Use durable sessions to continue work across turns, stream progress, and connect your own tools and MCP servers." That is a distinct product from the Agents SDK, the surface OpenAI adopted MCP into in March 2025; the Agents API is a newer, separate offering built around a managed Codex harness rather than the earlier SDK.

The Agents API overview guide describes the same capability in more detail: "Agents can operate in a sandbox where they can execute code, edit files, connect to MCP servers, and produce artifacts." Its code sample attaches a server as a tool of type mcp, naming it with a server_label field and pointing a transport of type http at a server_url, in the example https://developers.openai.com/mcp.

The linked MCP connections guide documents three ways to attach a server to agent.tools. An HTTP server with connection_origin set to "service" is reached directly by OpenAI and needs no session environment. An HTTP server with connection_origin set to "environment" is reached from the developer's own session environment instead, for servers on a private network. A server can also be started over stdio as a process inside that same session environment. The guide notes that omitting connection_origin defaults an HTTP connection to running through OpenAI.