1# Filesystem MCP
2npx @modelcontextprotocol/server-filesystem /path/to/allow
3 
4# PostgreSQL MCP
5npm install -g @modelcontextprotocol/server-postgres

claude config edit

1{
2  "mcpServers": {
3    "filesystem": {
4      "command": "npx",
5      "args": [
6        "@modelcontextprotocol/server-filesystem",
7        "/Users/you/projects"
8      ]
9    },
10    "postgres": {
11      "command": "mcp-server-postgres",
12      "env": {
13        "DATABASE_URL": "postgresql://user:pass@localhost/mydb"
14      }
15    }
16  }
17}

List all Python files modified this week in my project.

Show the schema for the users table.
Count how many users signed up this month.

List open issues labeled "bug" in our repo.
Create a PR for my current branch.

1// Before: Select this function
2function fetchUser(id: string) {
3  return fetch(`/api/users/${id}`)
4}
5 
6// After Cmd+K: "Add TypeScript types and error handling"
7async function fetchUser(id: string): Promise<User | null> {
8  try {
9    const response = await fetch(`/api/users/${id}`)
10    if (!response.ok) {
11      throw new Error(`HTTP ${response.status}`)
12    }
13    return await response.json()
14  } catch (error) {
15    console.error('Failed to fetch user:', error)
16    return null
17  }
18}

How does authentication work in this project?

Explain what this regex does.

What's the best way to add caching here?

Refactor all React components to use TypeScript.
Add proper prop types to each one.

Connect to the production database.
Show me the schema for the metrics table.
What data do we have for the last 30 days?

1I want to build a dashboard showing:
21. Daily active users
32. Revenue by product
43. Top converting pages
5 
6Think through how to implement this.

1Create a Next.js dashboard with three cards:
21. Daily Active Users - line chart
32. Revenue - bar chart by product
43. Top Pages - table with conversion rates
5 
6Use the metrics schema you saw earlier.
7Use Tailwind and Recharts.

Add loading state and error handling

Create a commit for the dashboard feature.
Push and create a PR.

1// my-mcp/src/index.ts
2import { Server } from '@modelcontextprotocol/sdk/server/index.js'
3import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js'
4 
5const server = new Server({
6  name: 'my-custom-mcp',
7  version: '1.0.0',
8})
9 
10// Define tools
11server.setRequestHandler('tools/call', async (request) => {
12  if (request.params.name === 'my_tool') {
13    const { input } = request.params.arguments
14 
15    // Your logic here
16    const result = await processInput(input)
17 
18    return {
19      content: [{
20        type: 'text',
21        text: JSON.stringify(result)
22      }]
23    }
24  }
25})
26 
27// Start server
28const transport = new StdioServerTransport()
29await server.connect(transport)

1server.setRequestHandler('tools/call', async (request) => {
2  if (request.params.name === 'get_weather') {
3    const { city } = request.params.arguments
4 
5    const response = await fetch(
6      `https://api.weather.com/v1?q=${city}&key=${API_KEY}`
7    )
8    const data = await response.json()
9 
10    return {
11      content: [{
12        type: 'text',
13        text: `Weather in ${city}: ${data.temp}°F, ${data.conditions}`
14      }]
15    }
16  }
17})

1{
2  "mcpServers": {
3    "weather": {
4      "command": "node",
5      "args": ["/path/to/my-mcp/build/index.js"],
6      "env": {
7        "API_KEY": "your-key"
8      }
9    }
10  }
11}

What's the weather in San Francisco?

1# Check MCP status
2claude mcp list
3 
4# View logs
5claude mcp logs <server-name>
6 
7# Restart
8claude mcp restart <server-name>

1{
2  "mcpServers": {
3    "name": {
4      "command": "executable",
5      "args": ["arg1", "arg2"],
6      "env": {
7        "KEY": "value"
8      }
9    }
10  }
11}