What is the key difference between X402 Middleware and Plugin?

X402 Middleware belongs to the Finance & Fintech category with local stdio execution, while Plugin belongs to the Finance & Fintech category with cloud HTTP/SSE execution.

How do I install X402 Middleware or Plugin in Claude Desktop or Cursor?

Copy the mcpServers JSON configuration snippet provided on this page into your claude_desktop_config.json or ~/.cursor/mcp.json file and restart your AI client.

Are X402 Middleware and Plugin free or paid?

X402 Middleware operates under a Free / Open Source model (No auth required). Plugin operates under a Free / Open Source model (No auth required).

Which MCP server has more tools and community activity?

X402 Middleware lists 0 tools with 0 views and 0 GitHub stars. Plugin lists 0 tools with 0 views and 0 GitHub stars.

Can I use both X402 Middleware and Plugin together in the same MCP host?

Yes! MCP hosts like Claude Desktop, Cursor, Windsurf, Cline, and VS Code support configuring multiple servers under the mcpServers object simultaneously.

How do I install X402 Middleware or Plugin in Claude Desktop, Cursor, or Windsurf?

Both servers follow the standard Model Context Protocol configuration format. Simply copy the JSON block from the configuration section above and paste it into your AI client's mcpServers configuration object (for instance in claude_desktop_config.json or ~/.cursor/mcp.json ), then completely restart or refresh the application.

Are X402 Middleware and Plugin free to use, or do they require API keys?

X402 Middleware is listed under a Free / Open Source model with No auth required . Plugin operates under a Free / Open Source model with No auth required . If environment variables are required (such as API keys), be sure to define them under the env key in your MCP client's configuration file.

Can I run both X402 Middleware and Plugin at the same time in my AI client?

Yes! MCP clients support multi-server orchestration. You can include both x402-middleware and plugin as distinct keys inside the single mcpServers object in your configuration file. Your AI assistant will automatically select and call the appropriate tool from either server during chat sessions.

Which MCP server has higher directory engagement and quality ratings?

On AllMCPs, X402 Middleware has a Quality Score of 29 /100 ( Emerging ) with 0 views, 0 installs, and 0 GitHub stars. Plugin holds a Quality Score of 45 /100 ( Fair ) with 0 views, 0 installs, and 0 GitHub stars.

Side-by-Side Model Context Protocol Comparison

X402 Middleware vs Plugin

In-depth architectural comparison of the X402 Middleware and Plugin MCP servers. Compare execution transports, security boundaries, tool capabilities, quality scores, and ready-to-paste client installation snippets for Claude, Cursor, Windsurf, and VS Code.

At a Glance & Executive Verdict

X402 Middleware

Finance & Fintech · Local stdio

Quality: 29/100 (Emerging) | Auth: No auth required

Plugin

Finance & Fintech · Remote HTTP/SSE

Quality: 45/100 (Fair) | Auth: No auth required

Verdict Summary: Choose X402 Middleware if you need specialized Finance & Fintech tools running via a local process. Choose Plugin if your workspace requires Finance & Fintech integration with remote web transport. Both servers can be configured concurrently in your client's mcpServers manifest.

Which MCP Server Should You Choose?

Choose X402 Middleware when:

You need dedicated capabilities in the Finance & Fintech domain.
You prefer local stdio subprocess transport architecture.
Your security boundary fits: No auth required (Free / Open Source).

Explore X402 Middleware Details

Choose Plugin when:

You need dedicated capabilities in the Finance & Fintech domain.
You prefer remote streaming HTTP/SSE transport architecture.
Your security boundary fits: No auth required (Free / Open Source).

Explore Plugin Details

Feature & Specification Comparison

Specification	X X402 Middleware Finance & Fintech	Plugin Finance & Fintech
Summary	One-line x402 + Stripe payment middleware for MCP servers. The Stripe for the agent economy.	Circulara Observe MCP plugin - meters your AI agents' token spend and carbon, free tier.
Category & Scope	Finance & Fintech	Finance & Fintech
Quality signal

Tools & Capabilities Breakdown

X402 Middleware Tools (0)

No explicit tool names declared in metadata yet. Check project README on main listing page.

Plugin Tools (0)

No explicit tool names declared in metadata yet. Check project README on main listing page.

Ready-to-Paste Client Configurations

Paste either (or both) of these JSON server blocks into your client config file (e.g. claude_desktop_config.json or ~/.cursor/mcp.json).

X402 Middleware Configuration

mcpServers (Claude Desktop / Cursor)

{
  "mcpServers": {
    "x402-middleware": {
      "command": "npx",
      "args": [
        "-y",
        "x402-middleware"
      ]
    }
  }
}

Plugin Configuration

mcpServers (Claude Desktop / Cursor)

{
  "mcpServers": {
    "plugin": {
      "url": "http://127.0.0.1:8787"
    }
  }
}

Frequently Asked Questions

X402 Middleware is categorized under Finance & Fintech and uses a local stdio subprocess. In contrast, Plugin belongs to Finance & Fintech using remote streaming HTTP/SSE transport. Select X402 Middleware when you need capabilities focused on finance & fintech and Plugin when you require tools for finance & fintech.

More alternatives to X402 Middleware More alternatives to Plugin Finance & Fintech category hub Canonical compare URL

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