Nacos Mcp Router

What is Nacos Mcp Router about?

Enables discovery and utilization of MCP servers through powerful search capabilities, automatic installation of stdio or SSE servers, and proxying of these services via HTTP. It operates in two modes: router (default) for recommendation, distribution, and installation, and proxy for converting SSE/stdio MCP servers into streamable HTTP endpoints.

How to use Nacos Mcp Router?

1. Set required environment variables – at minimum NACOS_ADDR, NACOS_USERNAME, and NACOS_PASSWORD.
2. Choose a deployment method:
   • uvx (recommended): uvx nacos-mcp-router@latest
   • pip: pip install nacos-mcp-router && python -m nacos_mcp_router
   • Docker: docker run -i --rm --network host -e NACOS_ADDR=$NACOS_ADDR -e NACOS_USERNAME=$NACOS_USERNAME -e NACOS_PASSWORD=$NACOS_PASSWORD -e TRANSPORT_TYPE=$TRANSPORT_TYPE nacos/nacos-mcp-router:latest
   • npx (TypeScript/Node.js): use the configuration in the serverConfig section.
3. Configure optional settings such as COMPASS_API_BASE, SEARCH_MIN_SIMILARITY, SEARCH_RESULT_LIMIT, TRANSPORT_TYPE, MODE, etc., via environment variables.
4. Interact via MCP client libraries – e.g., call searchMcpServer("Find MCP servers for NLP", ["nlp","language"]) to retrieve matching servers and their tools.

Key Features

• Dual operating modes: router (default) and proxy (enabled with MODE=proxy).
• Multi‑provider search: Nacos provider (service discovery + vector similarity) and optional Compass provider for semantic ranking.
• Configurable search: minimum similarity, result limit, and custom API endpoint.
• Tool integration: auto‑expose search_mcp_server, add_mcp_server, and use_tool for LLM agents.
• Multiple deployment options: uvx, pip, Docker, and npm (npx).
• Streamable HTTP conversion for SSE/stdio servers.

Use Cases

• LLM agents needing to discover and invoke external MCP services without hard‑coding endpoints.
• Microservice platforms that want dynamic registration and routing of AI model services.
• Developers building applications that require semantic search across a registry of MCP servers.
• Cloud environments where Nacos is already used for service discovery and configuration.

FAQ

Q: Do I need a Compass API key? A: No key is required for the default endpoint https://registry.mcphub.io; you can override it with COMPASS_API_BASE.

Q: What transport protocols are supported? A: stdio, sse, and streamable_http. Set TRANSPORT_TYPE accordingly.

Q: How do I switch to proxy mode? A: Set MODE=proxy and provide PROXIED_MCP_NAME (the target server registered in Nacos).

Q: Can I limit the number of search results? A: Yes, using SEARCH_RESULT_LIMIT.

Q: Which environment variables are mandatory? A: NACOS_PASSWORD is required; NACOS_ADDR and NACOS_USERNAME have defaults.

nacos-mcp-router: A MCP server that provides functionalities such as search, installation, proxy, and more.

Overview

Nacos is an easy-to-use platform designed for dynamic service discovery and configuration and service management. It helps you to build cloud native applications and microservices platform easily.

This MCP(Model Context Protocol) Server provides tools to search, install, proxy other MCP servers, with advanced search capabilities including vector similarity search and multi-provider result aggregation.

Nacos-MCP-Router has two working modes:

Router mode: The default mode, which recommends, distributes, installs, and proxies the functions of other MCP Servers through the MCP Server, helping users more conveniently utilize MCP Server services.

Proxy mode: Specified by the environment variable MODE=proxy, it can convert SSE and stdio protocol MCP Servers into streamable HTTP protocol MCP Servers through simple configuration.

Search Features

Nacos-MCP-Router provides powerful search capabilities through multiple providers:

Search Providers

1. Nacos Provider

   • Searches MCP servers using Nacos service discovery
   • Supports keyword matching and vector similarity search
   • Integrated with the local Nacos instance

2. Compass Provider

   • Connects to a COMPASS API endpoint for enhanced search
   • Supports semantic search and relevance scoring
   • Configurable API endpoint (default: https://registry.mcphub.io)

Search Configuration

Configure search behavior using environment variables:

# YOUR COMPASS API endpoint (for Outer Provider called Compass Provider)
COMPASS_API_BASE=https://registry.mcphub.io

# Minimum similarity score for results (0.0 to 1.0)
SEARCH_MIN_SIMILARITY=0.5

# Maximum number of results to return
SEARCH_RESULT_LIMIT=10

Search API

The search functionality is available through the MCP interface:

// Search for MCP servers
const results = await searchMcpServer(
  "Find MCP servers for natural language processing",
  ["nlp", "language"]
);

Results include:

• Server name and description
• Provider information
• Relevance score
• Additional metadata

Quick Start

Python

router mode

Tools

1. search_mcp_server
   • Search MCP servers by task and keywords.
   • Input:
     • task_description(string): Task description
     • key_words(string): Keywords of task
   • Returns: list of MCP servers and instructions to complete the task.
2. add_mcp_server
   • Add a MCP server. If the MCP server is a stdio server, this tool will install it and establish connection to it. If the MCP server is a sse server, this tool will establish connection to it
   • Input:
     • mcp_server_name(string): The name of MCP server.
   • Returns: tool list of the MCP server and how to use these tools.
3. use_tool
   • This tool helps LLM to use the tool of some MCP server. It will proxy requests to the target MCP server.
   • Input:
     • mcp_server_name(string): The target MCP server name that LLM wants to call.
     • mcp_tool_name(string): The tool name of target MCP server that LLM wants to call.
     • params(map): The parameters of the MCP tool.
   • Returns: Result returned from the target MCP server.

Usage

Using uv (recommended)

When using uv no specific installation is needed. We will use uvx to directly run nacos-mcp-router.

export NACOS_ADDR=127.0.0.1:8848
export NACOS_USERNAME=nacos
export NACOS_PASSWORD=$PASSWORD
uvx nacos-mcp-router@latest

Using PIP

Alternatively you can install nacos-mcp-router via pip:

pip install nacos-mcp-router

After installation, you can run it as a script using（As an example，Nacos is deployed in standalone mode on the local machine）:

export NACOS_ADDR=127.0.0.1:8848
export NACOS_USERNAME=nacos
export NACOS_PASSWORD=$PASSWORD
python -m nacos_mcp_router

Using Docker

docker run -i --rm --network host -e NACOS_ADDR=$NACOS_ADDR -e NACOS_USERNAME=$NACOS_USERNAME -e NACOS_PASSWORD=$NACOS_PASSWORD -e TRANSPORT_TYPE=$TRANSPORT_TYPE nacos/nacos-mcp-router:latest

Usage with Cline、Cursor、Claude and other applications

Add this to MCP settings of your application:

• Using uvx

{
    "mcpServers":
    {
        "nacos-mcp-router":
        {
            "command": "uvx",
            "args":
            [
                "nacos-mcp-router@latest"
            ],
            "env":
            {
                "NACOS_ADDR": "<NACOS-ADDR>, optional, default is 127.0.0.1:8848",
                "NACOS_USERNAME": "<NACOS-USERNAME>, optional, default is nacos",
                "NACOS_PASSWORD": "<NACOS-PASSWORD>, required"
            }
        }
    }
}

You may need to put the full path to the uvx executable in the command field. You can get this by running which uvx on MacOS/Linux or where uvx on Windows.

• Using docker

{
  "mcpServers": {
    "nacos-mcp-router": {
      "command": "docker",
      "args": [
        "run", "-i", "--rm", "--network", "host",  "-e", "NACOS_ADDR=<NACOS-ADDR>", "-e",  "NACOS_USERNAME=<NACOS-USERNAME>", "-e", "NACOS_PASSWORD=<NACOS-PASSWORD>" ,"-e", "TRANSPORT_TYPE=stdio", "nacos/nacos-mcp-router:latest"
      ]
    }
  }
}

Proxy Mode

The proxy mode supports converting SSE and stdio protocol MCP Servers into streamable HTTP protocol MCP Servers.

Usage

The usage of proxy mode is similar to that of router mode, with slightly different parameters. Docker deployment is recommended.

docker run -i --rm --network host -e NACOS_ADDR=$NACOS_ADDR -e NACOS_USERNAME=$NACOS_USERNAME -e NACOS_PASSWORD=$NACOS_PASSWORD -e TRANSPORT_TYPE=streamable_http -e MODE=proxy -e PROXIED_MCP_NAME=$PROXIED_MCP_NAME  nacos/nacos-mcp-router:latest

Environment Variable Settings

Parameter	Description	Default Value	Required	Remarks
NACOS_ADDR	Nacos server address	127.0.0.1:8848	No	the Nacos server address, e.g., 192.168.1.1:8848. Note: Include the port.
NACOS_USERNAME	Nacos username	nacos	No	the Nacos username, e.g., nacos.
NACOS_PASSWORD	Nacos password	-	Yes	the Nacos password, e.g., nacos.
COMPASS_API_BASE	COMPASS API endpoint for enhanced search	https://registry.mcphub.io	No	Override the default COMPASS API endpoint
SEARCH_MIN_SIMILARITY	Minimum similarity score (0.0-1.0)	0.5	No	Filter search results by minimum similarity score
SEARCH_RESULT_LIMIT	Maximum number of results to return	10	No	Limit the number of search results
NACOS_NAMESPACE	Nacos Namespace	public	No	Nacos namespace, e.g. public
TRANSPORT_TYPE	Transport protocol type	stdio	No	transport protocol type. Options: stdio, sse, streamable_http.
PROXIED_MCP_NAME	Proxied MCP server name	-	No	In proxy mode, specify the MCP server name to be converted. Must be registered in Nacos first.
MODE	Working mode	router	No	Available options: router, proxy.
PORT	Service port when TRANSPORT_TYPE is sse or streamable_http	8000	No
ACCESS_KEY_ID	Aliyun ram access key id	-	No
ACCESS_KEY_SECRET	Aliyun ram access key secret	-	No

typescript

Usage with Cline、Cursor、Claude and other applications

{
  "mcpServers": {
    "nacos-mcp-router": {
      "command": "npx",
      "args": [
        "nacos-mcp-router@latest"
      ],
      "env": {
        "NACOS_ADDR": "<NACOS-ADDR>, optional, default is 127.0.0.1:8848",
        "NACOS_USERNAME": "<NACOS-USERNAME>, optional, default is nacos",
        "NACOS_PASSWORD": "<NACOS-PASSWORD>, required"
      }
    }
  }
}

License

nacos-mcp-router is licensed under the Apache 2.0 License. This means you are free to use, modify, and distribute the software, subject to the terms and conditions of the Apache 2.0 License. For more details, please see the LICENSE file in the project repository.