transports-wg/meetings/2026-06-24_weekly.md

2026-06-24 MCP: Transport Working Group (Weekly)

TL;DR

The working group established an advancement strategy for the streaming Specification Enhancement Proposal (SEP) draft and debated introducing client-generated conversation correlation IDs to address routing and billing concerns. Shaun Smith from Hugging Face presented the streaming pull request, leading to discussions about task interaction and JSON RPC over Server-Sent Events (SSE) challenges. Ladi Bitto from Microsoft proposed an agnostic conversation identifier to resolve costly routing workarounds in Copilot Studio, which Kurtis Van Gent agreed to synthesize into a formal problem statement for core maintainers. Due to upcoming conferences and holidays, the next weekly meeting was canceled.

Detailed Summary

Streaming Brief and Task Interaction

• Shaun Smith (Hugging Face) presented a Specification Enhancement Proposal (SEP) pull request to address tool-calling streaming capabilities, particularly for multimodal scenarios, to allow higher-resolution execution steering and progress tracking.
• Mark Roth raised concerns about how streaming would interact with existing tasks (e.g., handling cancellation cases) and suggested that streaming capabilities might be built directly into tasks rather than introducing a distinct mechanism.
• Shaun Smith noted that the protocol must clearly instruct users on when to use streaming versus tasks, or whether tasks themselves should be extended.

JSON RPC and Server-Sent Events (SSE) Challenges

• Kurtis Van Gent raised a technical concern regarding how auto-streaming would work with JSON RPC, as JSON RPC typically requires a complete message before processing.
• Luca Chang noted that while the current events primitive streams standalone JSON RPC messages over an SSE stream, it does not manage event association or ordering.
• Mark Roth pointed out that a unidirectional SSE stream presents challenges for cancellation and bidirectional steering (e.g., redirecting sub-agents running in tool-calling loops).
• The group agreed that concrete use cases, user journeys, and tool designs must be documented early to ensure core maintainer alignment. Shaun Smith plans to have a mergeable brief ready in two weeks.

Client-Generated Conversation Correlation IDs

• Ladi Bitto (Microsoft) proposed introducing a client-generated conversation correlation or thread ID to resolve routing issues and support session management without re-introducing full protocol-level session handling.
• Kurtis Van Gent explained that changing the protocol for the current release version is impossible because that ship has sailed, but it could target a future version. He noted that core maintainers previously voted to remove sessions, so a very strong case is required.
• Ladi Bitto and Shaun Smith discussed why Peter's proposed "state handles" are insufficient, noting they are non-deterministic and introduce significant financial costs due to extra tool calls, especially impacting platforms like Microsoft Copilot Studio.
• Mike Kistler suggested quantifying the exact frequency and financial costs of these state handle workarounds to present a stronger case to core maintainers.
• Kurtis Van Gent committed to writing a structured problem statement summarizing the user journeys and technical limitations of state handles, to be reviewed by the working group before presenting to core maintainers.
• Gabriel Zimmerman offered to brainstorm arguments internally, and agreed to share Catie McCaffrey's contact information with Ladi Bitto to ensure Microsoft's routing and cost concerns are represented in core maintainer discussions.

SDK Release Readiness

• Mark Roth requested an update on SDK preparation for the upcoming July specification release.
• Kurtis Van Gent shared a support matrix showing that the Go and C# SDKs are closest to completion, which Mike Kistler celebrated.
• Kurtis Van Gent added that Python SDK development is actively progressing inside a 2.0 feature branch and is further along than the dashboard shows.

Next Steps & Timeline

The next weekly meeting has been canceled due to the AI Engineer World's Fair, holidays, and external time off. The group will resume in two weeks. In the interim, Shaun Smith will incorporate feedback into the streaming brief and refine the tool designs. Kurtis Van Gent will develop database and pagination examples for the streaming brief and draft a problem statement document summarizing the correlation ID use cases. Ladi Bitto will work on summarizing Microsoft's correlation ID use cases and cost factors, while Gabriel Zimmerman will provide Catie McCaffrey's contact information.

Action Items

• Shaun Smith Update the streaming brief document incorporating comments, pushing back on Peter's resources suggestion, and creating tool designs.
• Kurtis Van Gent Develop database and pagination examples for the streaming brief.
• Kurtis Van Gent Cancel next week's meeting and post a cancellation notice in the Discord channel.
• Kurtis Van Gent Write a problem statement document summarizing the correlation ID use cases and the technical limitations of state handles.
• Ladi Bitto Summarize the correlation ID use cases and provide a concise summary of the financial cost factors of the state handle workarounds.
• Gabriel Zimmerman Share Catie McCaffrey's contact information with Ladi Bitto.