Who should use Lex API?

Lex API is an open-source project built for legal researchers, AI developers, and public-sector technologists.

Does Lex API have a free plan?

Yes — Lex API is free to use.

What platforms does Lex API run on?

Lex API runs on the web, the command line, and API.

Is Lex API still active?

Unverified. Lex API has not been re-checked since it entered the index, so there is no finding either way — and only a positive finding would say otherwise.

What are alternatives to Lex API?

Similar projects tracked by PulseGate include LEX AI, Lexum.ai, and Lexi.

Who develops Lex API?

Lex API is developed by i.AI, based in the United Kingdom.

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Lex API

Name: Lex API
Author: i.AI

ai.gov.ukInfrastructure🇬🇧

Lex API is an experimental API for searching comprehensive UK legislation from legislation.gov.uk. It provides semantic search over Acts and Statutory Instruments and supports Model Context Protocol integrations for AI assistants and developer tools.

FreeMITWebCLIAPICloud-managed

Visit ai.gov.uk

65stars

31forks

10features

2025since

Overview

10 features

In the API design, testing & docs space, Lex API takes a focused approach. It focuses on finding and integrating authoritative UK legislation into legal research workflows and AI agents. Lex API is an open-source project aimed at legal researchers, AI developers, and public-sector technologists. It is available for free. It runs on the web, the command line, and API.

Behind Lex API is i.AI, based in the United Kingdom, and it first shipped in 2025. The project is developed in the open on GitHub with 65 stars. Key capabilities include Semantic Search, Legislation Search, and Relevance Ranking. It exposes integrations via an MCP server. Lex API is currently in beta.

Summary written by a language model from the project’s public pages.

Semantic Search
Legislation Search
Relevance Ranking
API Documentation
MCP Integration
Claude Desktop Setup
Claude Code Skill
Cursor Integration
VS Code Integration
Rate Limiting

Built with & integrations

Framework

FastAPI

AI providers

openai

Connectors

MCPvscode

Runs on

BrowserCLIAPI-onlyCloud-managed

Trust & compliance

License

MIT

Verified signals

HTTPSFree tierGitHub · ★ 65

Indexing history

What PulseGate has recorded for this listing

Indexed26 Aug · 17:57 UTC
i-dot-ai/lex verified via GitHub Search (Smart)
Source: GitHub Search (Smart) · Open

Frequently asked questions about Lex API

What is Lex API?: Lex API focuses on finding and integrating authoritative UK legislation into legal research workflows and AI agents. It is catalogued under API design, testing & docs on PulseGate.
Who should use Lex API?: Lex API is an open-source project built for legal researchers, AI developers, and public-sector technologists.
Does Lex API have a free plan?: Yes — Lex API is free to use.
What platforms does Lex API run on?: Lex API runs on the web, the command line, and API.
Is Lex API still active?: Unverified. Lex API has not been re-checked since it entered the index, so there is no finding either way — and only a positive finding would say otherwise.
What are alternatives to Lex API?: Similar projects tracked by PulseGate include LEX AI, Lexum.ai, and Lexi.LEX AI Lexum.ai Lexi
Who develops Lex API?: Lex API is developed by i.AI, based in the United Kingdom.
How long has Lex API been around?: Lex API first shipped in 2025.

At a glance

Pricing: Free
Platforms: API · CLI · Web
Languages: English
Open source: Yes · ★ 65
License: MIT
Status: 🟡 Beta
Built for: legal researchers, AI developers, and public-sector technologists
Model: Open source
Solves: Finding and integrating authoritative UK legislation into legal research workflows and AI agents.

Registered as

GitHub: i-dot-ai/lex

Developer

🇬🇧i.AI

Small team

GitHub

Open source

View on GitHub

Stars: 65
Forks: 31
Open issues: 10
Last commit: 26 Aug 2026
Commits 90d: 0
Contributors: 5
Authorship: Small team
Default branch: main
Latest release: v1.1.0 · 23 Mar 2026

Index record

Indexed: 26 Aug 2026
Lifecycle: Alive
Last seen: 26 Aug 2026

Identity audit (13)

Slug: i-dot-ai-lex-ai-gov-uk
Lifecycle state recorded: 26 Aug 2026
Verification state: Indexed for public listing
Listing state: Listed: yes
Index status: Included in index
Latest evidence snapshot: 26 Aug 2026
Timeline basis: Indexed-at chronology. This listing's first-seen date was written by the catalog backfill, not observed here, so it is not treated as a sighting.
Name from: Derived from the project's own page and URL.
Category from: Assigned by a language model.
Summary from: Written by a language model from public pages.
Languages from: Detected by a language model, checked against the page's own declaration.
Last updated: 26 Aug 2026
Canonical URL: https://lex.lab.i.ai.gov.uk/

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