Model Context Protocol

Structured context interfaces for optimal model comprehension.

Available for

Rust
TypeScript
Python

cargo add legion-mcp

Read the spec in the registry Talk to the team

model-context-protocol.tsTypeScript

1import { server, resource } from "@legionedge/mcp";
2 
3const docs = resource("docs", { schema: DocSchema });
4 
5server({ resources: [docs] })
6  .tool("search", SearchInput, async (q) => index.query(q))
7  .listen();

Version: v1.5
Status: Stable
License: Open specification
Implementations: Rust · TypeScript · Python
Stack layer: Context

What the spec defines

The guarantees, not the vibes.

Typed resources — context arrives as schema-validated data, not string glue
Tool definitions declared once, not re-sent every turn
Prompt templates as data, versioned alongside the spec
Conformance-tested across Rust, TypeScript, and Python

Overview

Why it's built this way.

Spec, schemas and conformance suite

The Model Context Protocol defines structured interfaces for feeding context to language models: typed resources, tool definitions, and prompt templates that models comprehend reliably, replacing the ad-hoc string concatenation that most applications still ship.

Structure pays twice. Models read validated, predictable context more reliably — and applications stop re-sending boilerplate every turn. Our field study of production MCP traffic found tool-definition overhead and redundant re-sends were two of the three largest sources of context waste; declare-once semantics remove both.

Tavoc's context assembly is built on the protocol end to end: scoped repository views arrive as typed resources, tools are declared at session start, and every context decision is inspectable in the session log.

Implementations are available for Rust, TypeScript, and Python, all conformance-tested against the same spec suite. The spec and the field-study data behind its design decisions are in the research registry.

Proven in production

If a protocol can't survive contact with a real product, it isn't finished. This one ships inside Tavoc.

Tavoc

Works with

The full stack

Implement it

Implementing the Model Context Protocol?

The conformance suite is public, and the team that wrote the spec reads its issue tracker. Independent implementations are the point.

Talk protocols with us Browse the registry

Model Context Protocol

The guarantees, not the vibes.

Why it's built this way.

If a protocol can't survive contact with a real product, it isn't finished. This one ships inside Tavoc.

Designed to compose.

Implementing the Model Context Protocol?