JSON Schema Manager MCP server

This MCP server manages JSON schemas and allows you to create instances from them, providing a simple way to define data structures and generate data that conforms to those structures.

Installation

You can install the MCP server using pip:

pip install mcp[cli]

After installation, you have two options to run the server:

1. Run it directly via Python:

python server.py

2. Install it with Claude Desktop:

mcp install server.py

Resources

The MCP server provides access to the following resources:

• schema://{schema_id} - Retrieve a specific schema by its ID
• schemas://list - Get a list of all available schemas on the server

Creating and Using Schemas

Creating a JSON Schema

You can create a new JSON schema using the create_schema tool:

// Create a schema for a person
create_schema(
  title="Person",
  properties={
    "name": {"type": "string"},
    "age": {"type": "integer"},
    "email": {"type": "string", "format": "email"}
  },
  required=["name", "email"]
)

This creates a new schema with:

• A title of "Person"
• Three properties: name (string), age (integer), and email (string with email format)
• Two required fields: name and email

Creating Schema Instances

Once you have a schema, you can create instances that conform to it using the create_instance tool:

// Create a person instance
create_instance(
  schema_id="<schema-id-from-previous-step>",
  values={
    "name": "John Doe",
    "age": 30,
    "email": "[email protected]"
  }
)

Replace <schema-id-from-previous-step> with the actual ID returned when you created the schema.

Available Tools

The server provides two main tools:

• create_schema - For defining new JSON schemas
• create_instance - For generating JSON instances based on a specified schema with custom values

How to add this MCP server to Cursor

There are two ways to add an MCP server to Cursor. The most common way is to add the server globally in the ~/.cursor/mcp.json file so that it is available in all of your projects.

If you only need the server in a single project, you can add it to the project instead by creating or adding it to the .cursor/mcp.json file.

Adding an MCP server to Cursor globally

To add a global MCP server go to Cursor Settings > MCP and click "Add new global MCP server".

When you click that button the ~/.cursor/mcp.json file will be opened and you can add your server like this:

{
    "mcpServers": {
        "cursor-rules-mcp": {
            "command": "npx",
            "args": [
                "-y",
                "cursor-rules-mcp"
            ]
        }
    }
}

Adding an MCP server to a project

To add an MCP server to a project you can create a new .cursor/mcp.json file or add it to the existing one. This will look exactly the same as the global MCP server example above.

How to use the MCP server

Once the server is installed, you might need to head back to Settings > MCP and click the refresh button.

The Cursor agent will then be able to see the available tools the added MCP server has available and will call them when it needs to.

You can also explictly ask the agent to use the tool by mentioning the tool name and describing what the function does.