What is the key difference between Blackwall X402 Guardrail and Plugin?

Blackwall X402 Guardrail belongs to the Finance & Fintech category with cloud HTTP/SSE execution, while Plugin belongs to the Finance & Fintech category with cloud HTTP/SSE execution.

How do I install Blackwall X402 Guardrail 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 Blackwall X402 Guardrail and Plugin free or paid?

Blackwall X402 Guardrail 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?

Blackwall X402 Guardrail 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 Blackwall X402 Guardrail 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 Blackwall X402 Guardrail 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 Blackwall X402 Guardrail and Plugin free to use, or do they require API keys?

Blackwall X402 Guardrail 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 Blackwall X402 Guardrail and Plugin at the same time in my AI client?

Yes! MCP clients support multi-server orchestration. You can include both blackwall-x402-guardrail 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, Blackwall X402 Guardrail has a Quality Score of 42 /100 ( Fair ) 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

Blackwall X402 Guardrail vs Plugin

In-depth architectural comparison of the Blackwall X402 Guardrail 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

Blackwall X402 Guardrail

Finance & Fintech · Remote HTTP/SSE

Quality: 42/100 (Fair) | Auth: No auth required

Plugin

Finance & Fintech · Remote HTTP/SSE

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

Verdict Summary: Choose Blackwall X402 Guardrail if you need specialized Finance & Fintech tools running via a hosted cloud SSE transport. 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 Blackwall X402 Guardrail 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 Blackwall X402 Guardrail 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	B Blackwall X402 Guardrail Finance & Fintech	Plugin Finance & Fintech
Summary	Pre-signature x402 payment verdict (GO/HOLD/STOP) for AI agents, with a verifiable signed receipt.	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

Blackwall X402 Guardrail 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).

Blackwall X402 Guardrail Configuration

mcpServers (Claude Desktop / Cursor)

{
  "mcpServers": {
    "blackwall-x402-guardrail": {
      "url": "https://blackwalltier.com"
    }
  }
}

Plugin Configuration

mcpServers (Claude Desktop / Cursor)

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

Frequently Asked Questions

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

More alternatives to Blackwall X402 Guardrail More alternatives to Plugin Finance & Fintech category hub