Docs
Documentation
How Lexnus works, what the words mean, and how to connect a surface to the engine. Start with the loop below — everything else is reference.
Start here
Three steps from an empty account to your policy being enforced. No implementation project, no configuration call.
Build a playbook from a contract you already have
Upload one signed contract or one Word template. Lexnus reads it, extracts the clauses and the standards implicit in the language — the liability cap you accept, the governing law you prefer, the clauses you always include — and drafts a playbook.
A lawyer on your team reviews it, adjusts what is wrong, and publishes. Nothing is enforced until a human publishes it.
Analyse a counterparty contract against it
Upload inbound paper. The engine extracts the Smart Fields your rules reference, evaluates every rule, and returns a verdict per rule: pass or fail, with the contract language that caused it.
The result is written to the record, tied to the exact playbook version that produced it.
Connect a surface
Point another tool at the same engine. The application, the Word add-in, or an AI agent over MCP all ask the same question and get the same answer — because the playbook, not the surface, decides.
See Surfaces for what is live and what is on the roadmap.
Concepts
Seven words carry the whole model. Getting these right makes everything else obvious.
| Clause | A unit of approved contract language, reviewed and published by a lawyer. Clauses live in the Clause Library. Nothing outside the library gets assembled into a contract. |
| Rule | A plain-language condition your policy requires, written once. Aggregate liability must not exceed 1.5x annual contract value. Rules reference Smart Fields, so the comparison is precise rather than interpretive. |
| Playbook | A governed set of rules and clauses that defines one legal policy — your NDA standard, your MSA standard. A published playbook is immutable. Editing it creates a new version. |
| Smart Field | A structured data point extracted from contract text: a cap amount, a notice period, a governing law. The AI extracts the value. The rule evaluates it. |
| Analysis | One contract evaluated against one playbook. Also the unit your plan meters. |
| Verdict | The result of one rule against one contract: pass or fail. Deterministic. There is no score, no confidence, no suggestion — the playbook decides, not the model. |
| The record | The append-only history of what was asked, what was answered, and which frozen policy version answered it. This is what makes a decision defensible a year later. |
Surfaces
A surface is anywhere a contract question can be asked. Every surface calls the same engine, so the answer does not change with the tool.
API and MCP reference
The MCP reference is the complete technical document: all 23 tools with JSON Schema, the authentication model, scopes, rate limits and the audit behaviour of every write. The essentials:
| Server URL | https://app.lexnus.com/mcp |
| Transport | Streamable HTTP. Stateless — every call is authenticated independently. |
| Authentication | OAuth 2.1 authorisation code flow, or a personal access token issued in Lexnus |
| Scopes | lexnous:read, lexnous:write |
| Tools | 23 — twelve read, eleven write |
| Tool manifest | GET https://app.lexnus.com/mcp/tools |
| Rate limit | 5 requests per second sustained per account, burst 20 |
| Analysis | Asynchronous. Trigger, then poll for the result. |
MCP integration overview covers the same ground for a non-engineering reader.
Feature guides
Security and legal
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