Justin Spahr-Summers

Justin Spahr-Summers co-invented the Model Context Protocol and helped establish its architecture and governance. His work is foundational reading for why MCP separates hosts, clients and servers.

Original profile or publication ↗

MCP governance identifies Justin as a co-inventor and lead maintainer emeritus; portrait comes from the linked public GitHub profile. Checked September 19, 2026.

Referenced in 101

1. MCP 101

   MCP base protocol ↗

   MCP is a stateful JSON-RPC protocol with initialization, negotiated capabilities, notifications and explicit lifecycle behavior.

2. MCP 101

   MCP server primitives ↗

   Servers can expose prompts, resources and tools; treating all three as interchangeable functions throws away useful protocol semantics.

3. MCP 101

   MCP tools specification ↗

   Tool schemas describe inputs and outputs, but the client still owns consent, presentation and safety around invocation.

4. MCP 101

   MCP client best practices ↗

   Clients must treat servers as untrusted capability providers, preserve user control and make tool state and failures understandable.

5. MCP 101

   Governance and stewardship ↗

   MCP uses named maintainers, decision roles and public processes rather than letting protocol direction hide inside one vendor's product roadmap.

About this page

This is a Mudpie reference profile, not an account, endorsement or claim that Justin Spahr-Summers contributed to Mudpie. The profile identifies an author, editor, maintainer, speaker or source publication connected to the linked work; it is not necessarily the article byline. Summaries are Mudpie's; the linked work remains the source of truth.