NacosMcpRouter 1.0.0

nacos-mcp-router

A .NET 10 MCP server that searches, installs, and proxies MCP servers registered in Nacos.

<p> <a href="./README.md">English</a> | <a href="./README_cn.md">简体中文</a> </p>

Overview

Nacos provides service discovery, configuration management, and service management for cloud-native applications. nacos-mcp-router uses Nacos to discover MCP servers and exposes tools for searching, connecting to, and proxying them.

The supported implementation is .NET 10. The router accepts MCP connections over streamable_http and can proxy downstream stdio or mcp-streamable servers.

Quick Start

stdio

export NACOS_ADDR=127.0.0.1:8848
export NACOS_USERNAME=nacos
export NACOS_PASSWORD=nacos
bash src/scripts/download-model.sh  # Defaults to ModelScope (CN mirror); override with HF_ENDPOINT
dotnet run --project src/NacosMcpRouter

streamable_http

export NACOS_ADDR=127.0.0.1:8848
export NACOS_USERNAME=nacos
export NACOS_PASSWORD=nacos
export TRANSPORT_TYPE=streamable_http
export PORT=8000
dotnet run --project src/NacosMcpRouter

The MCP endpoint is available at http://localhost:8000/mcp.

Cluster deployment notes:

• /mcp only accepts MCP 2026-07-28+ clients (older clients get 400 / -32022).
• Upstream MCP servers may use stdio or mcp-streamable; the router itself accepts inbound connections over streamable_http only.
• mcp-streamable services may define OAuth under agentConfig.mcpServers.<name>.oauth. client_credentials acquires tokens automatically; authorization_code and device_code require completing user authorization externally and then setting authorizationCode or deviceCode. While authorization is pending, use_tool returns verification instructions instead of blocking indefinitely.
• For services created from Nacos registration details, set MCP_OAUTH_CONFIG to a JSON object keyed by MCP server name. Keep client secrets out of source control and logs.
• Vector storage defaults to SonnetDB. For a cluster, set VECTOR_STORE=postgres and point every instance at the same PostgreSQL database with pgvector.
• If an old .data directory contains stdio server indexes, delete it and restart to rebuild the indexes.
• GET /health returns 200 {"status":"healthy"}.

Docker

docker build -t nacos-mcp-router-dotnet src
docker run -i --rm --network host \
  -e NACOS_ADDR=$NACOS_ADDR \
  -e NACOS_USERNAME=$NACOS_USERNAME \
  -e NACOS_PASSWORD=$NACOS_PASSWORD \
  nacos-mcp-router-dotnet

For streamable_http, add -p 8000:8000 and set TRANSPORT_TYPE=streamable_http and PORT=8000.

On first start the container downloads the ONNX model (about 86 MB) from ModelScope. Mount a pre-populated model directory to skip the download:

docker run -i --rm --network host \
  -v "$PWD/models:/app/models" \
  -e NACOS_ADDR=$NACOS_ADDR \
  -e NACOS_USERNAME=$NACOS_USERNAME \
  -e NACOS_PASSWORD=$NACOS_PASSWORD \
  nacos-mcp-router-dotnet

Tools

• search_mcp_server(task_description, key_words)
• add_mcp_server(mcp_server_name)
• use_tool(mcp_server_name, mcp_tool_name, params)

See the MCP Router tools workflow Skill for the complete discovery, installation, and invocation flow.

Environment Variables

The model download scripts also read:

Architecture

See the .NET router design.

License

nacos-mcp-router is licensed under the Apache 2.0 License. See LICENSE for details.