MCP Skill

Connect any Model Context Protocol (MCP) server to your agent. The MCP skill discovers tools, resources, and prompts from external servers and makes them available as native agent tools.

Overview

MCP is the general-purpose integration path for tool ecosystems. Instead of writing custom skills for each service, point the MCP skill at any MCP-compatible server and its tools become available to your agent automatically.

The skill supports multiple transport types (SSE, HTTP, WebSocket), automatic reconnection, and background capability refresh.

Configuration

import { BaseAgent } from 'webagents';
import { MCPSkill } from 'webagents/skills/mcp';

const agent = new BaseAgent({
  name: 'mcp-agent',
  model: 'openai/gpt-4o',
  skills: [
    new MCPSkill({
      servers: [
        {
          name: 'weather',
          url: 'https://weather-mcp.example.com/mcp',
          transport: 'sse',
        },
        {
          name: 'database',
          url: 'https://db-mcp.example.com/mcp',
          transport: 'http',
          auth: { type: 'bearer', token: process.env.DB_MCP_TOKEN! },
        },
      ],
      timeout: 30_000,
      reconnectInterval: 60_000,
    }),
  ],
});

Config Reference

Parameter (Python / TS)	Type	Default	Description
`servers`	list	`[]`	MCP server definitions
`timeout` / `timeout`	seconds (Py) / ms (TS)	30 / 30 000	Request timeout
`reconnect_interval` / `reconnectInterval`	seconds (Py) / ms (TS)	60 / 60 000	Reconnect delay
`max_connection_errors` / `maxConnectionErrors`	int	5	Errors before giving up on a server
`capability_refresh_interval` / `capabilityRefreshInterval`	seconds (Py) / ms (TS)	300 / 300 000	Capability re-discovery cadence

Server Config

Field	Required	Description
`name`	Yes	Identifier for this server
`url`	Yes	Server endpoint URL
`transport`	No	`sse`, `http`, or `websocket` (default: `sse`)
`auth`	No	Authentication config (`{ type: 'bearer', token: '...' }`)

How It Works

On initialization, the skill connects to each configured MCP server and discovers its capabilities:

Tools are registered as agent tools — the LLM can call them directly.

Resources are exposed for data retrieval.

Prompts are available for prompt injection.

The skill runs background tasks for health monitoring and capability refresh, automatically reconnecting if a server goes down.

Platform MCP Proxy

When running on the Robutler platform, agents can also access MCP servers through the platform's proxy at /api/integrations/mcp/{provider}. The proxy handles authentication for connected accounts (Google, n8n, etc.) and supports tool-level pricing with _metering.

See the MCP Integration Guide for platform-specific setup.

Dynamic Tool Registration

Skills can register additional MCP servers at runtime:

import { Skill, tool } from 'webagents';

class MySkill extends Skill {
  readonly name = 'my-skill';

  @tool({ description: 'Dynamically add an MCP server' })
  async addServer(params: { name: string; url: string }): Promise<string> {
    const mcp = this.agent!.skills.find((s) => s.name === 'mcp') as MCPSkill;
    await mcp.registerServer({ name: params.name, url: params.url });
    return `Connected to ${params.name}`;
  }
}