Support MCP Python SDK v2 and the MCP 2026-07-28 protocol

[zhuziqi97]

Describe the feature

MCP Python SDK 2.0.0 is now stable and supports the MCP 2026-07-28 protocol.

The current openai-agents main branch still requires:

mcp>=1.19.0,<2

This upper bound prevents downstream projects from upgrading to MCP Python SDK v2 and using the modern protocol path through OpenAI Agents.

We understand that MCP v2 servers can continue serving legacy initialize clients, so many existing integrations may still work through the compatibility path. This issue is specifically about native MCP v2 support in OpenAI Agents, including compatibility with the stable v2 package and the 2026-07-28 protocol.

Background

PR #3989 previously attempted an MCP v2 migration. It was closed with the recommendation to revisit the work in a fresh PR after MCP v2 became stable, with a clearly defined supported scenario and regression coverage for existing transport contracts.

MCP Python SDK v2 has now reached a stable release, but we could not find a follow-up issue or PR tracking the migration.

Could the maintainers clarify:

1. Whether MCP Python SDK v2 and MCP 2026-07-28 support is planned.
2. Whether a new implementation PR would be welcome after the intended compatibility scope is confirmed.

References

• MCP Python SDK v2.0.0:
  https://github.com/modelcontextprotocol/python-sdk/releases/tag/v2.0.0
• Previous migration attempt:
  feat: Add compatibility with MCP Python SDK v2 (mcp 2.0.0b2) #3989
• MCP 2026-07-28 changes:
  https://modelcontextprotocol.io/specification/2026-07-28/changelog

[seratch]

Thanks for sharing this. We'll definitely support MCP SDK v2, but it was released only two days ago, and we'd like to take some time before starting implementation. Please hold off on submitting PRs for now.

[mixxer]

I‘m waiting for this so long.