feat: add 2026-06-17 weekly meeting notes (#44)

meetings/2026-06-17_weekly.md

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+# 2026-06-17 MCP: Transport Working Group (Weekly)
+
+## TL;DR
+
+The meeting focused on resolving key architectural questions around metadata
+internationalization, session state persistence for legacy systems, and tracing
+standards, characterized by a collaborative yet highly analytical vibe as the
+team balanced protocol simplification against complex enterprise constraints.
+
+## Detailed Summary
+
+### Metadata Internationalization & Language Negotiation
+* Sam Morrow presented a proposal to standardize internationalization for
+  user-facing strings in the Model Context Protocol (MCP) by mirroring HTTP
+  `Accept-Language` headers within MCP metadata (e.g., the `_meta` field),
+  ensuring compatibility across both HTTP and non-HTTP transports.
+* Shaun Smith and Peter Alexander expressed strong reservations about
+  translating tool descriptions and parameters, arguing that doing so alters
+  tokenization and could unpredictably affect model behavior. Sam Morrow
+  countered that while tool schema field names and identifiers must remain
+  static, server authors should not be strictly prohibited from
+  internationalizing tool descriptions or responses if their specific use cases
+  demand it.
+* Kurtis Van Gent raised concerns about managing "two sources of truth" (the
+  HTTP header and payload metadata) when routing requests, as a failure to keep
+  them in sync could break routing assumptions or introduce security
+  vulnerabilities. Sam Morrow advocated for an opt-in validation approach where
+  servers only validate headers if they actively consume them, preventing
+  requests from failing on non-internationalized servers.
+* Mark Roth raised concerns about how per-request language negotiation affects
+  caching predictability. Luca Chang and Sam Morrow noted that utilizing the
+  standard HTTP `Vary: Accept-Language` header is the established path for CDNs
+  and server-side caching and should be explicitly respected.
+* The group decided to formalize the internationalization proposal as a
+  Specification Enhancement Proposal (SEP) on the Transport Working Group
+  repository. Sam Morrow will update the draft to more cleanly define the
+  translation "threshold scope" (where translation starts and stops) based on
+  the group's feedback.
+
+### Session State, Affinity, and Telemetry in Legacy Architectures
+* Ladi Bitto (Microsoft) raised concerns regarding the recent removal of the
+  initialization handshake and session ID headers, noting that it is a breaking
+  change for Microsoft Dynamics finance and operations servers.
+* The Microsoft Dynamics backend relies on legacy stateful UI workflows
+  requiring persistent "kernel sessions" on the server. Without a protocol-level
+  session ID, load balancers cannot guarantee that parallel calls from the same
+  client will land on the same stateful server instance. Luca Chang added that
+  Amazon Bedrock faces a similar challenge where session IDs are required to pin
+  virtual machines to avoid customer isolation issues and cold start latencies.
+* Kurtis Van Gent and Peter Alexander suggested using explicit state
+  handles—where an initialization tool call returns a state ID that must be
+  explicitly passed into subsequent tool calls. Ladi Bitto argued this approach
+  is problematic because it relies on the model's non-deterministic ability to
+  pass handles correctly, adds latency, and increases billing costs for
+  customers who are charged per tool call by clients like Microsoft Copilot
+  Studio.
+* Ladi proposed a client-generated "conversation ID" for telemetry and routing.
+  Kurtis Van Gent cautioned that any such ID needs strict protocol-defined
+  boundaries (when it starts and stops) to avoid reintroducing the session
+  tracking complexities that led to the removal of sessions in the first place,
+  especially when threading to sub-agents or forking conversations.
+* Core maintainers reiterated that sessions were removed because their
+  architectural complexity outweighed their benefits. The burden of proof
+  remains on Ladi Bitto and the group to provide concrete, play-by-play request
+  flows and justifications demonstrating why explicit state handles cannot solve
+  their specific use cases before any protocol-level changes can be aligned
+  upon.
+
+### OpenTelemetry and Tracing Standards
+* Andreas Schlapbach suggested examining existing trace standards, specifically
+  OpenTelemetry, as a potential model for managing sub-agents. He noted that
+  OpenTelemetry's hierarchical trace structure (opening a parent and routing
+  children using a hierarchy of correlation IDs) could provide a stable, clean
+  framework for routing and telemetry without protocol-level sessions.
+
+### Remote Server Proxying & Standard I/O Reliability
+* Sam Morrow proposed a temporary workaround for servers requiring persistent
+  state by building a thin wrapper server to proxy requests and manage session
+  state locally. Kurtis Van Gent, Shaun Smith, and Peter Alexander strongly
+  rejected this approach, identifying it as an anti-pattern that inherits all
+  the flaws of poorly-defined session lifetimes.
+* Kurtis Van Gent highlighted that different tools currently handle standard I/O
+  processes inconsistently (some spawning one process per user, others one per
+  conversation). The group agreed to advise users against relying on standard
+  I/O for state management until it is better defined.
+
+## Next Steps & Timeline
+
+Between now and the next meeting, Shaun Smith will update the meeting notes to
+add the link to the streaming problem statement. Sam Morrow will open a pull
+request for the internationalization Specification Enhancement Proposal on the
+transport working group repository and refine the proposal language to define
+translation thresholds. Ladi Bitto will work on finding official documentation
+on Microsoft tool call billing and authoring play-by-play request flow examples.
+The group will work together to document explicit stateful use cases that cannot
+be handled via the current stateless protocol to present to core maintainers.
+
+## Action Items
+
+* [ ] **Shaun Smith** Add the link to the streaming problem statement in the
+  meeting notes.
+* [ ] **Sam Morrow** Open a pull request for the internationalization
+  Specification Enhancement Proposal on the transport working group repository.
+* [ ] **Sam Morrow** Refine the proposal language to clearly define the
+  threshold and scope for content translation.
+* [ ] **Ladi Bitto** Find and share documentation confirming that some clients
+  bill per individual tool call.
+* [ ] **Ladi Bitto** Provide concrete play-by-play examples of request flows and
+  explain why current state handles do not resolve the identified issues.
+* [ ] **The group** Document clear use cases that cannot be performed in the
+  current protocol to challenge the existing decision on session removal.
+* [ ] **The group** Present the identified use cases to core maintainers to
+  verify that they are important and justify protocol changes.