Model Context Protocol (MCP)

Benched.ai Editorial Team

The Model Context Protocol (MCP) is a proposed standard for packaging prompt context, retrieval data, and safety instructions into a structured JSON envelope.

MCP Envelope Fields

Field	Type	Purpose
version	string	Protocol version e.g. 1.0
system	string	Safety & persona instructions
retrieval	array	Evidence documents with citations
memory	string	User profile summary
user	string	Latest user request

Benefits

Benefit	Explanation
Determinism	Identical envelope → reproducible output
Auditing	Each field logged separately
Tooling	Lint & validation against JSON Schema

Current Trends (2025)

Draft IETF MCP spec open for comments.
SDKs auto-build MCP envelopes from LangChain chains.
Gateways sign MCP envelopes to prevent tampering in transit.

Implementation Tips

Embed SHA-256 of retrieval docs to detect drift.
Compress large retrieval arrays with zstd-base64.
Include expires_at to force context refresh.