MCP

MCP

Model Context Protocol integration for connecting agents with external tools and services

Overview

MCP (Model Context Protocol) enables Astreus agents to connect with external tools and services seamlessly. Define MCP servers as simple objects with automatic environment variable loading and use them at different levels - agent, task, or conversation level.

Creating MCP Servers

Define MCP servers as array objects with automatic environment loading:

import { Agent } from '@astreus-ai/astreus';

// Define MCP servers array
const mcpServers = [
  {
    name: 'github',
    command: "npx",
    args: ["-y", "@modelcontextprotocol/server-github"]
    // GITHUB_PERSONAL_ACCESS_TOKEN loaded from .env automatically
  },
  {
    name: 'filesystem', 
    command: "npx",
    args: ["-y", "@modelcontextprotocol/server-filesystem", "/Users/username/Documents"]
  }
];

const agent = await Agent.create({
  name: 'DevAgent',
  model: 'gpt-4'
});

// Add MCP servers to agent
await agent.addMCPServers(mcpServers);

// Use automatically in conversations
const response = await agent.ask("List my repositories and save to repos.txt");

Example

Here's a complete example showing MCP integration:

import { Agent } from '@astreus-ai/astreus';

// Create agent
const agent = await Agent.create({
  name: 'DevAssistant',
  model: 'gpt-4',
  systemPrompt: 'You are a helpful development assistant with access to various tools.'
});

// Add MCP servers
await agent.addMCPServers([
  {
    name: 'github',
    command: "npx", 
    args: ["-y", "@modelcontextprotocol/server-github"]
  },
  {
    name: 'filesystem',
    command: "npx",
    args: ["-y", "@modelcontextprotocol/server-filesystem", "/path/to/project"]
  },
  {
    name: 'search',
    command: "npx",
    args: ["-y", "@modelcontextprotocol/server-brave-search"]
  }
]);

// Agent now has access to GitHub, filesystem, and search tools
const response = await agent.ask(`
  Check my latest repositories, 
  create a summary file in my project directory,
  and search for TypeScript best practices
`);

console.log(response);

Environment Variables

MCP servers automatically load environment variables from your .env file:

# .env
GITHUB_PERSONAL_ACCESS_TOKEN=ghp_xxxxxxxxxxxx
BRAVE_API_KEY=your_brave_api_key
GOOGLE_APPLICATION_CREDENTIALS=/path/to/credentials.json

No need to specify environment variables in code - they're loaded automatically and securely.

Server Types

Local Servers (stdio)

For servers that run as local processes:

const localServers = [
  {
    name: 'sqlite',
    command: "npx",
    args: ["-y", "@modelcontextprotocol/server-sqlite", "--db-path", "/path/to/db.sqlite"],
    cwd: "/working/directory"
  }
];

Remote Servers (SSE)

For servers that connect via HTTP/SSE:

const remoteServers = [
  {
    name: 'api-server',
    url: "https://api.example.com/mcp/events"
  }
];

Multi-Level Usage

Agent Level

Available for all tasks and conversations:

// Agent-level: Available everywhere 
await agent.addMCPServers([
  {
    name: 'filesystem',
    command: "npx",
    args: ["-y", "@modelcontextprotocol/server-filesystem", "/Users/username/Documents"]
  }
]);

Task Level

Available for specific tasks:

// Task-level: Available for this task only
const task = await agent.createTask({
  prompt: "Analyze my GitHub repositories",
  mcpServers: [
    {
      name: 'github',
      command: "npx",
      args: ["-y", "@modelcontextprotocol/server-github"]
    }
  ]
});

Conversation Level

Available for single conversations:

// Conversation-level: Available for this conversation only
const response = await agent.ask("Search for TypeScript news", {
  mcpServers: [
    {
      name: 'search',
      command: "npx",
      args: ["-y", "@modelcontextprotocol/server-brave-search"]
    }
  ]
});

Manual Tool Access

Access MCP tools programmatically:

// List available MCP tools
const tools = agent.getMCPTools();
console.log('Available MCP tools:', tools.map(t => t.name));

// Call specific MCP tool
const result = await agent.callMCPTool('github:list_repos', {
  owner: 'username'
});

MCP integration provides powerful external tool access while maintaining security and simplicity.

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