Cards
A typed corpus of physics, chemistry, biology, climate, math, engineering and numerical-method principles. Each declares a TeX formula, conventions, expected limits, optional validation envelopes, and references.
Lemma
A schema-validated cards corpus, a verification engine, and an MCP server. Open under MIT / CC-BY 4.0 / Apache-2.0. Used by any agent that writes scientific code.
Build science on proven ground
A lemma is a small proven proposition you build theorems on. Lemma is the open corpus of proven cards every scientific result can stand on — and the engine that checks any output against them.
Engine
A check runner that scores candidate output against the cards — per-check severity, not one scalar — plus a hypothesis cross-check engine for AI-proposed novel principles.
MCP server
@artano-ai/mcp-server exposes the engine over the Model Context Protocol.
Claude Code, Cursor, Codex — any MCP-aware runtime. Verification becomes a
tool call.
Python SDK
artano-lemma reads the same corpus in-process. A notebook calls Lemma
without the MCP protocol or a Node subprocess. Same cards, same verdicts.
Where to next
Quickstart
Install, register, and run your first verification — in five minutes.
Cards & schema
What a card is and how the corpus is validated — the unit of meaning.