Skip to content

What if MCP was Symmetric? - Jerome Swannack, Anthropic#

MCP Dev Summit North America 2026 digest Program Wildcard pick 2–3 April 2026

Abstract

Jerome Swannack, Member of Technical Staff, Anthropic (helped build MCP at Anthropic)

  • Why: A protocol-design thought experiment from one of MCP's builders — the kind of "what if" that occasionally becomes the next protocol revision, and useful for anyone who has to reason about where MCP goes next.
  • What: An exploration of what would become possible if servers could call tools from clients — inverting MCP's current asymmetric model where only clients invoke server tools (from abstract only; the program description is a single line, so depth is unknown).
  • How: Conceptual/speculative session on protocol symmetry, not a deployed feature.
  • Where applicable: Protocol watchers and anyone designing MCP-adjacent infrastructure; no immediate operational applicability.