MCP Servers

How agents access external tools and data through the Model Context Protocol.

What is MCP?

MCP (Model Context Protocol) is how agents access external tools. An MCP server exposes a set of tools (functions) that the agent can call during a run. muxAI manages which MCP servers each agent can access.

Built-in servers

muxAI ships with several MCP servers out of the box:

Server	Tools	Purpose
news-analyst	RSS feeds, CoinMarketCap news	Fetch and analyze crypto news
chart-analyst	Chart image analysis	Analyze trading charts from URLs
orchestrator	run_team, ask_reporter, get_my_decisions	Coordinate team members (lead agents only) and recall past decisions with outcomes
contractor	ask_contractor, list_contractors	Consult external LLM contractors
wallet	wallet_address, wallet_fetch	Agent wallet access and x402 payments
docs	search_docs, get_doc_page	Search and read muxAI platform documentation

Built-in servers are registered in config/mcp-registry.json and automatically available when an agent uses Built-in MCP mode.

Custom servers

Add your own MCP servers through the MCP Servers page. Two transport types are supported:

stdio

Runs as a local process. You provide the command and arguments. The agent communicates over stdin/stdout.

Example: a Python script that wraps a proprietary API.

HTTP

Connects to a remote server via URL. Optionally include authentication headers.

Example: an MCP server running on another machine or cloud service.

Adding a custom server

Paste JSON

Paste a standard MCP config JSON block. muxAI parses it, shows a preview, and imports all servers at once.

{
  "mcpServers": {
    "my-server": {
      "command": "node",
      "args": ["path/to/server.js"]
    }
  }
}

Manual

Fill in the fields: name, command/URL, arguments, optional headers, and description.

MCP modes

Each agent is configured with one of two MCP modes:

Mode	Behavior
Built-in (default)	Agent gets only the built-in servers plus any custom servers from the database. Uses --mcp-config and --strict-mcp-config flags for full isolation.
Global	Agent inherits MCP servers from your global Claude CLI config (~/.claude). No isolation flags.

Built-in mode is recommended. It prevents global MCP servers from leaking into agent runs and ensures reproducible behavior.

How it works at runtime

When an agent runs in Built-in mode, muxAI:

1. Reads the built-in registry (config/mcp-registry.json)
2. Loads custom servers from the database
3. Merges them into a single MCP config JSON
4. Passes it to the Claude CLI via --mcp-config <path> --strict-mcp-config

The agent can only call tools from servers in that config. Nothing else.

Guides

Add a Custom MCP Server

Connect an existing MCP server through the portal UI. No code changes required.

Build a Built-in MCP Server

Create a new MCP server package that ships with your muxAI installation.