Fetch Jsonpath MCP

🚀 Fetch JSONPath MCP

A Model Context Protocol (MCP) server that offers tools for fetching and extracting JSON data from URLs using JSONPath patterns. This helps in reducing LLM token usage and minimizing hallucination by extracting only the necessary data.

🚀 Quick Start

This MCP server enables you to extract and fetch JSON data from URLs with JSONPath patterns. It is highly efficient as it allows you to get only the data you need, saving tokens and reducing model hallucination.

✨ Features

• Reduce LLM Token Usage & Hallucination: Instead of fetching entire JSON responses and wasting tokens, extract only the data you need.
• Multiple Installation Options: Can be installed in various IDEs like Claude Code, Cursor, Windsurf, and VS Code.
• Rich Toolset: Provides tools such as get-json, get-text, batch-get-json, and batch-get-text for different data extraction needs.
• JSONPath Support: Uses jsonpath-ng for JSONPath implementation, allowing flexible data extraction.
• Performance Benefits: Offers token efficiency, faster processing, reduced hallucination, cost savings, and better focus.

🎯 Why Use This?

Reduce LLM Token Usage & Hallucination - Instead of fetching entire JSON responses and wasting tokens, extract only the data you need.

Traditional Fetch vs JSONPath Extract

❌ Traditional fetch (wasteful):

// API returns 2000+ tokens
{
  "data": [
    {
      "id": 1,
      "name": "Alice",
      "email": "alice@example.com", 
      "avatar": "https://...",
      "profile": {
        "bio": "Long bio text...",
        "settings": {...},
        "preferences": {...},
        "metadata": {...}
      },
      "posts": [...],
      "followers": [...],
      "created_at": "2023-01-01",
      "updated_at": "2024-01-01"
    },
    // ... 50 more users
  ],
  "pagination": {...},
  "meta": {...}
}

✅ JSONPath extract (efficient):

// Only 10 tokens - exactly what you need!
["Alice", "Bob", "Charlie"]

Using pattern: data[*].name saves 99% tokens and eliminates model hallucination from irrelevant data.

📦 Installation

For most IDEs, use the uvx tool to run the server.

{
  "mcpServers": {
    "fetch-jsonpath-mcp": {
      "command": "uvx",
      "args": [
        "fetch-jsonpath-mcp"
      ]
    }
  }
}

claude mcp add fetch-jsonpath-mcp -- uvx fetch-jsonpath-mcp

{
  "mcpServers": {
    "fetch-jsonpath-mcp": {
      "command": "uvx",
      "args": ["fetch-jsonpath-mcp"]
    }
  }
}

{
  "mcpServers": {
    "fetch-jsonpath-mcp": {
      "command": "uvx",
      "args": ["fetch-jsonpath-mcp"]
    }
  }
}

"mcp": {
  "servers": {
    "fetch-jsonpath-mcp": {
      "type": "stdio",
      "command": "uvx",
      "args": ["fetch-jsonpath-mcp"]
    }
  }
}

💻 Usage Examples

Basic Usage

get-json

Extract JSON data using JSONPath patterns.

{
  "name": "get-json",
  "arguments": {
    "url": "http://localhost:8080",
    "pattern": "foo[*].baz"
  }
}

Returns: [1, 2]

get-text

Get raw text content from any URL.

{
  "name": "get-text",
  "arguments": {
    "url": "http://localhost:8080"
  }
}

Returns: {"foo": [{"baz": 1, "qux": "a"}, {"baz": 2, "qux": "b"}], "bar": {"items": [10, 20, 30], "config": {"enabled": true, "name": "example"}}, "metadata": {"version": "1.0.0"}}

batch-get-json

Process multiple URLs with different JSONPath patterns.

{
  "name": "batch-get-json",
  "arguments": {
    "requests": [
      {"url": "http://localhost:8080", "pattern": "foo[*].baz"},
      {"url": "http://localhost:8080", "pattern": "bar.items[*]"}
    ]
  }
}

Returns: [[1, 2], [10, 20, 30]]

batch-get-text

Get text content from multiple URLs.

{
  "name": "batch-get-text",
  "arguments": {
    "urls": ["http://localhost:8080", "http://localhost:8080"]
  }
}

Returns: ["JSON content...", "JSON content..."]

📚 Documentation

Demo Server Data

The demo server at http://localhost:8080 returns:

{
  "foo": [{"baz": 1, "qux": "a"}, {"baz": 2, "qux": "b"}],
  "bar": {
    "items": [10, 20, 30], 
    "config": {"enabled": true, "name": "example"}
  },
  "metadata": {"version": "1.0.0"}
}

JSONPath Examples

This project uses jsonpath-ng for JSONPath implementation.

For complete JSONPath syntax reference, see the jsonpath-ng documentation.

🚀 Performance Benefits

• Token Efficiency: Extract only needed data, not entire JSON responses
• Faster Processing: Smaller payloads = faster LLM responses
• Reduced Hallucination: Less irrelevant data = more accurate outputs
• Cost Savings: Fewer tokens = lower API costs
• Better Focus: Clean data helps models stay on task

Configuration

Set environment variables:

export JSONRPC_MCP_TIMEOUT=30
export JSONRPC_MCP_HEADERS='{"Authorization": "Bearer token"}'
export JSONRPC_MCP_PROXY="http://proxy.example.com:8080"

Development

# Run tests
pytest

# Check code quality
ruff check --fix

Development Setup

1. Install Dependencies

uv sync

2. Start Demo Server (Optional)

# Install demo server dependencies
uv add fastapi uvicorn

# Start demo server on port 8080
uv run demo-server

3. Run MCP Server

uv run fetch-jsonpath-mcp