LexLink

LexLink is an MCP server that exposes Korea’s National Law Information API to AI agents and LLM applications. It enables you to search, retrieve, and analyze Korean legal information through a comprehensive set of MCP tools, with robust error handling and UTF-8 Korean text support.

How to use

To use LexLink, run the MCP client that supports the MCP protocol, then connect to LexLink using the provided MCP endpoints. You can perform core law lookups, administrative rule queries, case law retrieval, and advanced AI-powered search to explore related laws and interpretations. Follow the quick-start flow to initialize the environment, set your OC identifier, and start the server in the transport mode you need.

How to install

Prerequisites: Python 3.10 or newer, and access to an MCP client that can communicate via MCP with LexLink.

Step-by-step setup as shown in the runtime instructions:

uv sync

# Stdio transport start (recommended for local development)
OC=your_oc uv run stdio

# HTTP transport start (for Kakao PlayMCP or similar)
OC=your_oc TRANSPORT=http uv run serve

# Example endpoints you will connect to as an MCP client
http://localhost:8000/sse

Configuration and runtime details

LexLink requires you to set an OC identifier to authenticate with the Korean National Law Information API. Configure this as an environment variable or pass it per-tool as shown in the examples.

# Environment variable (recommended)
export OC=your_id_here

# Per-tool override of OC
eflaw_search(query="법령명", oc="your_id_here")

# Stdio transport start with OC set
OC=your_oc uv run stdio

# HTTP transport start with OC and HTTP transport
OC=your_oc TRANSPORT=http uv run serve

Server endpoints:
- Stdio: uv run stdio
- HTTP: uv run serve

Troubleshooting and notes

If you encounter an error about the OC parameter, ensure you have set OC either as an environment variable or via per-tool arguments.

Korean characters are supported through UTF-8 encoding. If you see garbled text, make sure your terminal uses UTF-8 encoding.

For timeout issues, increase the timeout value in your environment.

If the server fails to start after dependency updates, re-sync dependencies to ensure compatibility.

Available tools

eflaw_search

Search laws by effective date with optional date range and pagination.

law_search

Search laws by announcement date and retrieve results.

eflaw_service

Retrieve full law content by effective date, including specific articles via the jo parameter.

law_service

Retrieve full law content by announcement date, including specific articles via the jo parameter.

eflaw_josub

Query specific articles/paragraphs by providing the law MST and article code.

law_josub

Query specific articles/paragraphs by providing the law MST and article code.

elaw_search

Search English-translated laws.

elaw_service

Retrieve full English-translated law content.

admrul_search

Search administrative rules such as ordinances, notices, and guidelines.

admrul_service

Retrieve full administrative rule content.

lnkLs_search

Search law-ordinance linkage for laws linked to local ordinances.

lnkLsOrdJo_search

Find ordinance articles linked to a specific law article.

lnkDep_search

Find laws linked to ordinances by government ministry.

drlaw_search

Retrieve law-ordinance linkage statistics.

lsDelegated_service

Retrieve information about delegated laws, rules, and ordinances.

prec_search

Search court precedents from Korean courts.

prec_service

Retrieve full text of a court precedent.

detc_search

Search Constitutional Court decisions.

detc_service

Retrieve full Constitutional Court decision text.

expc_search

Search legal interpretations issued by government agencies.

expc_service

Retrieve full legal interpretation text.

decc_search

Search administrative appeal decisions.

decc_service

Retrieve full administrative appeal decision text.

article_citation

Extract citations from a specific law article.

aiSearch

AI-powered semantic search for law articles with full text.

aiRltLs_search

AI-powered search for related laws semantically.