---
title: "Build on FOLIO"
canonical: "https://openlegalstandard.org/tools/build"
tools: [{"name":"MCP server","stage":"connect","maturity":"available","liveUrl":null,"repo":"https://github.com/alea-institute/folio-mcp","license":"MIT"},{"name":"Public API","stage":"connect","maturity":"available","liveUrl":"https://folio.openlegalstandard.org/docs","repo":"https://github.com/alea-institute/folio-api","license":"MIT"},{"name":"Python library","stage":"connect","maturity":"available","liveUrl":null,"repo":"https://github.com/alea-institute/folio-python","license":"MIT"},{"name":"FOLIO Propositions","stage":"connect","maturity":"available","liveUrl":null,"repo":"https://github.com/alea-institute/folio-propositions","license":"MIT"}]
---

# Build on FOLIO

The FOLIO ontology and all of its tools are free and open source. Pick the connection that fits your stack.

- [MCP server](https://openlegalstandard.org/tools/build#mcp)

## MCP server

INPUT: your agents and apps. OUTPUT: one shared set of 18,000+ legal tags they all speak.

Your agents talk to FOLIO's agents. Claude, Codex, and other MCP clients can search concepts, walk the hierarchy, and tag text.

Maturity: Available.



### Try it 

- [Try it](https://openlegalstandard.org/resources/folio-mcp)

- [Build with it](https://openlegalstandard.org/tools/build#build-mcp)

### Build with it 

- [Setup guide](https://openlegalstandard.org/resources/folio-mcp)
- [Tools reference](https://openlegalstandard.org/resources/folio-mcp-tools)
- [Source](https://github.com/alea-institute/folio-mcp)
- [GitHub repository](https://github.com/alea-institute/folio-mcp)


- [Public API](https://openlegalstandard.org/tools/build#api)

## Public API

Free and open to any origin. Fetch any concept as HTML, RDF, Markdown, or JSON.

Maturity: Available.



### Try it 

- [Try it](https://folio.openlegalstandard.org/docs)

- [Build with it](https://openlegalstandard.org/tools/build#build-api)

### Build with it 

- [Site guide](https://openlegalstandard.org/resources/folio-api)
- [Public API documentation](https://folio.openlegalstandard.org/docs)
- [Source and Docker setup](https://github.com/alea-institute/folio-api)
- [GitHub repository](https://github.com/alea-institute/folio-api)


- [Python library](https://openlegalstandard.org/tools/build#python)

## Python library

pip install folio-python, then search, query, and traverse the ontology in code.

Maturity: Available.



### Try it 

- [Try it](https://openlegalstandard.org/resources/folio-python-library)

- [Build with it](https://openlegalstandard.org/tools/build#build-python)

### Build with it 

- [Library guide](https://openlegalstandard.org/resources/folio-python-library)
- [Source and installation](https://github.com/alea-institute/folio-python)
- [GitHub repository](https://github.com/alea-institute/folio-python)


```bash
pip install folio-python
```



- [FOLIO Propositions](https://openlegalstandard.org/tools/build#propositions)

## FOLIO Propositions

The shared schema Enrich and Insights use to record legal propositions.

Maturity: Available.



### Try it 

- [Try it](https://github.com/alea-institute/folio-propositions)

- [Build with it](https://openlegalstandard.org/tools/build#build-propositions)

### Build with it 

- [Source and setup](https://github.com/alea-institute/folio-propositions)
- [GitHub repository](https://github.com/alea-institute/folio-propositions)


```bash
pip install folio-propositions
```



## The Ontology

Download FOLIO's 18,000+ concepts as FOLIO.owl (CC BY 4.0).

- [The Ontology](https://github.com/alea-institute/FOLIO)