Lex Remote MCP Server

A remote MCP server providing access to 63,000+ court cases and advanced legislation search with semantic capabilities.

Overview

Property	Value
URL	https://lex.lab.i.ai.gov.uk/mcp
Transport	HTTP (remote server)
API key	Not required
Local setup	None -- configured as a remote MCP endpoint
Maintained by	UK Government AI Lab (Incubator for AI, DSIT)

No Local Installation

Unlike the uk-legislation server, the Lex server runs remotely. You do not need to install or start anything locally. It is configured in .mcp.json and Claude Code connects to it over HTTP when needed.

Configuration

In .mcp.json:

{
  "mcpServers": {
    "lex": {
      "type": "http",
      "url": "https://lex.lab.i.ai.gov.uk/mcp"
    }
  }
}

Tools

The Lex server provides a broader set of tools compared to the local uk-legislation server, with a focus on case law, semantic search, and explanatory notes.

Legislation Search

Tool	Description
search_for_legislation_acts	Search for Acts of Parliament with semantic matching
search_for_legislation_sections	Search within specific sections of legislation
search_amendments	Find amendments affecting legislation
search_amendment_sections	Search within amendment text

Legislation Lookup

Tool	Description
lookup_legislation	Look up a specific piece of legislation by identifier
get_legislation_full_text	Retrieve the complete text of legislation
get_legislation_sections	Get all sections of a statute

Explanatory Notes

Tool	Description
search_explanatory_note	Search explanatory notes across legislation
get_explanatory_note_by_section	Get the explanatory note for a specific section
get_explanatory_note_by_legislation	Get all explanatory notes for a statute

What Are Explanatory Notes?

Explanatory notes are published alongside most Acts of Parliament. They explain the purpose and effect of each section in plain language. They are not part of the law itself but are invaluable for understanding legislative intent.

Data Proxy

Tool	Description
proxy_legislation_data	Proxy raw data requests to legislation.gov.uk

Server Status

Tool	Description
get_live_stats_api_stats_get	Live API statistics
health_check_healthcheck_get	Server health check

When Is Lex Used?

The Lex server complements the local uk-legislation server. Skills may use either or both depending on the task:

Need	Server	Why
Look up a specific statute	uk-legislation	Direct XML access, works offline
Check if a provision is in force	uk-legislation	Dedicated check_in_force tool
Search for case law	lex	63,000+ court cases with semantic search
Get explanatory notes	lex	Structured explanatory note access
Semantic legislation search	lex	AI-powered relevance ranking
Check amendments	Either	Both provide amendment tools

Comparison with Local Server

Feature	uk-legislation (local)	lex (remote)
Transport	stdio (local process)	HTTP (remote)
Data source	legislation.gov.uk XML	legislation.gov.uk + court cases
Court cases	No	Yes (63,000+)
Explanatory notes	No	Yes
Semantic search	No	Yes
In-force checking	Yes	No (dedicated tool)
Territorial extent	Yes	No (dedicated tool)
Offline capable	Yes (after cache)	No
Cache	24h in-memory	Server-side

Availability

The Lex server is hosted by the UK Government AI Lab. While generally available, it depends on external infrastructure. If the server is unreachable, skills that need case law or explanatory notes will fall back to what is available from the local uk-legislation server and the AI's training data.

Example Usage in Skills

When a skill like Legislation Tracker runs, it might call tools from both servers:

1. search_legislation (local) -- find the statute referenced in the contract
2. check_in_force (local) -- verify the statute is still in force
3. check_amendments (local) -- check for recent amendments
4. get_explanatory_note_by_section (lex) -- understand the purpose of a section
5. search_for_legislation_acts (lex) -- find related legislation via semantic search

This combination of local and remote MCP servers gives skills comprehensive, real-time access to UK legal data.