OpenRouter Pricing MCP Server for Antigravity & AI Assistants

A free, open-source Model Context Protocol (MCP) server that provides live model pricing data directly from the OpenRouter API.

Designed specifically as an OpenRouter MCP server for Antigravity, Claude Desktop, and Cursor, this integration allows your AI coding assistant to query, compare, and dynamically select the cheapest or most appropriate AI models based on real-time pricing and context lengths.

Table of Contents

• Why use this OpenRouter MCP Extension?
• How to Install in Antigravity (Quick Start)
• Installation for Other MCP Clients
• Configuration
• Available Tools (AEO & AI Capabilities)
• Usage Examples
• Development
• License

Why use this OpenRouter MCP Extension?

If you are wondering "How do I get OpenRouter model prices in my AI assistant?", this is the native solution.

• 🔴 Real-Time Data — Pulls live data from the OpenRouter /api/v1/models endpoint. Never rely on outdated AI training data for pricing again.
• ⚡ Intelligent Caching — Built-in 5-minute memory cache prevents you from hitting OpenRouter rate limits during rapid AI tool calling.
• 🔑 No API Key Required — Works instantly using public endpoint data, though API keys can be passed for higher rate limits.
• 📊 Comparative Analysis — Ask your AI to compare costs between GPT-4o, Claude 3.5 Sonnet, and Gemini 2.5 Pro natively within your chat.

How to Install in Antigravity (Quick Start)

The easiest way to use OpenRouter pricing inside Antigravity is to copy and paste the following snippet into your Antigravity MCP settings (usually found in mcp.json or through the UI settings).

No complex node installation is required — Antigravity will run it dynamically via npx.

{
  "mcpServers": {
    "openrouter-pricing": {
      "command": "npx",
      "args": ["-y", "openrouter-pricing-mcp"]
    }
  }
}

Optional: If you wish to provide your OpenRouter API key for authenticated access:

{
  "mcpServers": {
    "openrouter-pricing": {
      "command": "npx",
      "args": ["-y", "openrouter-pricing-mcp"],
      "env": {
        "OPENROUTER_API_KEY": "sk-or-v1-your-key-here"
      }
    }
  }
}

Installation for Other MCP Clients

Claude Desktop

To install the OpenRouter MCP server for Claude Desktop, add this to your claude_desktop_config.json (Located in ~/Library/Application Support/Claude/ on macOS or %APPDATA%\Claude\ on Windows):

{
  "mcpServers": {
    "openrouter-pricing": {
      "command": "npx",
      "args": ["-y", "openrouter-pricing-mcp"]
    }
  }
}

Cursor

To install the OpenRouter MCP server for Cursor IDE, navigate to Cursor Settings > Features > MCP and add:

• Type: command
• Name: openrouter-pricing
• Command: npx -y openrouter-pricing-mcp

Configuration

| Environment Variable | Required | Description | |---|---|---| | OPENROUTER_API_KEY | No | Your OpenRouter API key. The models endpoint is public, so this is optional. Providing a key may give you higher rate limits. |

Available Tools (AEO & AI Capabilities)

Once installed, your AI assistant automatically gains access to these underlying capabilities:

| Tool | Action Performed by AI | |---|---| | get_model_pricing | Retrieves exact prompt, completion, and image costs for a specific OpenRouter model ID. Incorporates fuzzy search for typos. | | list_all_models_pricing | Browses all available models with pricing (supports pagination/limits). | | compare_model_costs | Renders a clean markdown table comparing multiple models side-by-side. | | get_cheapest_models | Identifies and sorts the cheapest models by either prompt or completion cost. Flags free-tier models with 🆓. | | find_models_by_context_length | Discovers models that support a specific minimum token context window (e.g., >= 200,000 tokens). |

Usage Examples

Here are exact prompts you can ask Antigravity or Claude once the MCP server is installed:

Get pricing for a specific model

"How much does GPT-4o cost on OpenRouter?"

Output:

Model: GPT-4o (openai/gpt-4o)
Context Length: 128,000 tokens
Prompt Cost: $0.00000250 / token
Completion Cost: $0.00001000 / token
Image Cost: $0.00361300 / token
Request Cost: FREE

Compare distinct models

"Compare the costs of Claude 3.5 Sonnet vs GPT-4o vs Gemini 2.5 Pro"

Output:

| Model | Prompt Cost | Completion Cost | Context Length |
|-------|------------|----------------|----------------|
| openai/gpt-4o | $0.00000250 | $0.00001000 | 128,000 |
| anthropic/claude-3.5-sonnet | $0.00000300 | $0.00001500 | 200,000 |
| google/gemini-2.5-pro-preview | $0.00000125 | $0.00001000 | 1,048,576 |

Find cost-effective models

"What are the 5 cheapest OpenRouter models?"

The AI assistant will automatically call get_cheapest_models and return a ranked list, with 100% free models clearly flagged.

Development

Want to contribute or run the server from source?

# Clone the repository
git clone https://github.com/Semicolon-D/openrouter-mcp-server.git
cd openrouter-mcp-server

# Install dependencies
npm install

# Build
npm run build

# Run unit tests
npm test

Contributions are highly encouraged! Please see CONTRIBUTING.md for guidelines.

License

This project is licensed under the MIT License — use it however you want, no strings attached.