llm-tools-openapi

a plugins that allow to use OpenAPI as a tools

Installation

Install this plugin in the same environment as LLM.

llm install llm-tools-openapi

Usage

To use this with the LLM command-line tool:

llm --td --tool 'OpenAPIToolbox(openapi_url="https://your/swagger.json")' 'question your API'

With the LLM Python API:

import llm
from llm_tools_openapi import openapi

model = llm.get_model("gpt-4.1-mini")

result = model.chain(
    "Example prompt goes here",
    tools=[openapi]
).text()

Development

To set up this plugin locally, first checkout the code. Then create a new virtual environment:

cd llm-tools-openapi
python -m venv venv
source venv/bin/activate

Now install the dependencies and test dependencies:

llm install -e '.[test]'

To run the tests:

python -m pytest

Using MCP Servers as OpenAPI Tools with llm-tools-openapi

The llm-tools-openapi plugin is not limited to standard OpenAPI-compatible APIs. You can also use it to interact with any MCP (Model Context Protocol) server by converting it into an OpenAPI server using mcpo.

Why Use mcpo?

MCP servers typically communicate over raw stdio, which is not compatible with most tools and lacks standard features like authentication, documentation, and error handling. mcpo solves this by acting as a proxy: it exposes any MCP server as a RESTful OpenAPI HTTP server, instantly making it accessible to tools and agents that expect OpenAPI endpoints.

Benefits:

• Instantly compatible with OpenAPI tools, SDKs, and UIs
• Adds security, stability, and scalability
• Auto-generates interactive documentation for every tool
• Uses standard HTTP—no custom protocols or glue code required

How to Set Up

1. Start Your MCP Server with mcpo

mcpo also supports serving multiple MCP servers from a single config file. Each tool will be available under its own route, with its own OpenAPI schema and documentation.

Example demo/mcp-demo.json

{
    "mcpServers": {
        "basic-memory": {
            "command": "uvx",
            "args": [
                "basic-memory",
                "mcp"
            ]
        },        
        "playwright": {
            "command": "npx",
            "args": ["-y", "@playwright/mcp@latest"]
        }
    }
}

Start mcpo with:

mcpo --config demo/mcp-demo.json

Each tool will be accessible at:

• http://localhost:8000/basic-memory
• http://localhost:8000/playwright

And their OpenAPI docs at:

• http://localhost:8000/basic-memory/docs
• http://localhost:8000/playwright/docs

3. Use with llm-tools-openapi

Point the llm-tools-openapi plugin to the OpenAPI endpoint provided by mcpo. For example:

llm \
--td \
--tool 'OpenAPIToolbox(openapi_url="http://0.0.0.0:8000/playwright/openapi.json")' \
--tool 'OpenAPIToolbox(openapi_url="http://0.0.0.0:8000/basic-memory/openapi.json")' \
"Open Hacker News and create a note in News directory
For the ten first articles, create a note like this :
title - url
Number of upvote 
Number of comment 
use snapshot and not screenshot" --cl 30

You will obtain a md file with the content you want.

---
title: Hacker News - Top 5 Articles
type: note
permalink: hacker-news/hacker-news-top-5-articles
tags:
- '#news'
- '#technology'
---

1. **Deep learning gets the glory, deep fact checking gets ignored**  
   [Read more](https://rachel.fast.ai/posts/2025-06-04-enzyme-ml-fails/index.html)  
   Site: fast.ai  
   - Points: 73  
   - Author: chmaynard  
   - Comments: 5  
   - Posted: 55 minutes ago  

2. **Destination: Jupiter**  
   [Read more](https://clarkesworldmagazine.com/liptak_06_25/)  
   Site: clarkesworldmagazine.com  
   - Points: 52  
   - Author: AndrewLiptak  
   - Comments: 13  
   - Posted: 2 hours ago  

....

5. **A deep dive into self-improving AI and the Darwin-Gödel Machine**  
   [Read more](https://richardcsuwandi.github.io/blog/2025/dgm/)  
   Site: richardcsuwandi.github.io  
   - Points: 7  
   - Author: hardmaru  
   - Comments: Discuss  
   - Posted: 1 hour ago

Summary

By combining llm-tools-openapi with mcpo, you can:

• Instantly convert any MCP server into an OpenAPI-compatible API
• Manage and call MCP tools using standard OpenAPI workflows
• Leverage the full power of LLM agents and automation with minimal setup

For more details, see the mcpo documentation and the Open WebUI docs.