MCP Integration

Connect Amplifier to Model Context Protocol servers.

Overview

MCP (Model Context Protocol) is a standard for connecting AI assistants to external tools and data sources. Amplifier supports MCP servers, letting you:

  • Connect to databases - Query and modify data
  • Access APIs - Any service with MCP support
  • Use external tools - Capabilities from MCP ecosystem
  • Share tools - Same server works with multiple clients

What is MCP?

MCP separates: - Client - The AI assistant (Amplifier) - Server - Provider of tools/resources

Amplifier (Client) ←→ MCP Server ←→ External System

Benefits: - Standard protocol - Reusable servers - Ecosystem of tools - Works with multiple AI clients

Configuring MCP Servers

In Settings

# ~/.amplifier/settings.yaml
mcp:
  servers:
    - name: filesystem
      command: npx @modelcontextprotocol/server-filesystem
      args: ["/allowed/path"]

    - name: postgres
      command: npx @modelcontextprotocol/server-postgres
      env:
        DATABASE_URL: "postgresql://user:pass@localhost/db"

In Bundle

# bundle.yaml
mcp:
  servers:
    - name: my-server
      command: python my_server.py

Available MCP Servers

Official Servers

Server Purpose
@modelcontextprotocol/server-filesystem File operations
@modelcontextprotocol/server-postgres PostgreSQL queries
@modelcontextprotocol/server-sqlite SQLite databases
@modelcontextprotocol/server-github GitHub API

Installing Servers

# Via npm
npm install -g @modelcontextprotocol/server-filesystem
npm install -g @modelcontextprotocol/server-postgres

# Via pip
pip install mcp-server-fetch

Example: Filesystem Server

Configure

mcp:
  servers:
    - name: files
      command: npx @modelcontextprotocol/server-filesystem
      args: ["/home/user/projects"]

Use

The server adds tools that Amplifier can use:

> List files in /home/user/projects
> Read the contents of package.json

Example: Database Server

Configure

mcp:
  servers:
    - name: database
      command: npx @modelcontextprotocol/server-postgres
      env:
        DATABASE_URL: "postgresql://localhost/mydb"

Use

> Show all tables in the database
> Query the users table for active users
> Count orders from last week

Example: GitHub Server

Configure

mcp:
  servers:
    - name: github
      command: npx @modelcontextprotocol/server-github
      env:
        GITHUB_TOKEN: ${GITHUB_TOKEN}

Use

> List open PRs in microsoft/amplifier
> Get details of issue #123
> Show my recent commits

Creating MCP Servers

Python Server

# my_server.py
from mcp.server import Server
from mcp.types import Tool, TextContent

server = Server("my-server")

@server.tool()
async def get_weather(city: str) -> str:
    """Get weather for a city"""
    # Implementation
    return f"Weather in {city}: Sunny, 72°F"

@server.tool()
async def search_docs(query: str) -> str:
    """Search internal documentation"""
    # Implementation
    return f"Found 5 results for: {query}"

if __name__ == "__main__":
    server.run()

Register

mcp:
  servers:
    - name: my-tools
      command: python my_server.py

MCP Resources

MCP servers can also provide resources (data):

@server.resource("docs://{path}")
async def get_doc(path: str) -> str:
    """Get documentation by path"""
    with open(f"/docs/{path}") as f:
        return f.read()

Access in Amplifier:

> Get the resource docs://api/auth.md

Debugging MCP

Test Server Directly

# Run server
npx @modelcontextprotocol/server-filesystem /tmp

# In another terminal, test with mcp CLI
mcp test-server filesystem

Check Logs

# Amplifier logs MCP communication
export AMPLIFIER_LOG_LEVEL=debug
amp

Common Issues

Server not starting: - Check command path - Verify dependencies installed - Check environment variables

Tools not appearing: - Restart Amplifier - Verify server is running - Check server logs

Permission errors: - Check allowed paths - Verify credentials - Check environment setup

Security Considerations

Principle of Least Privilege

mcp:
  servers:
    # Good - limited scope
    - name: project-files
      command: npx @modelcontextprotocol/server-filesystem
      args: ["/home/user/current-project"]

    # Avoid - too broad
    - name: all-files
      command: npx @modelcontextprotocol/server-filesystem
      args: ["/"]  # Don't do this!

Credential Management

mcp:
  servers:
    - name: database
      command: npx @modelcontextprotocol/server-postgres
      env:
        # Use environment variable, not hardcoded
        DATABASE_URL: ${DATABASE_URL}

Audit MCP Actions

MCP tool calls appear in session logs:

cat events.jsonl | jq 'select(.tool_name | startswith("mcp:"))'

Try It Yourself

Exercise 1: Filesystem Server

# Add to ~/.amplifier/settings.yaml
mcp:
  servers:
    - name: files
      command: npx @modelcontextprotocol/server-filesystem
      args: ["./"]

npm install -g @modelcontextprotocol/server-filesystem
amp

> What files are in this directory?

Exercise 2: SQLite Server

mcp:
  servers:
    - name: db
      command: npx @modelcontextprotocol/server-sqlite
      args: ["./test.db"]

> Create a users table
> Insert some test data
> Query all users

Resources