# devtools-mcp 🛠️

**Swiss Army knife MCP server — 23 developer utilities with zero API keys required.**

Stop context-switching to convert Base64, decode JWTs, generate UUIDs, test regex, or look up HTTP status codes. `mcp-devtools-server` puts all these tools directly in your AI assistant.

[![npm version](https://img.shields.io/npm/v/mcp-devtools-server)](https://www.npmjs.com/package/mcp-devtools-server)
[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)

## Quick Start

### Claude Code
```bash
claude mcp add devtools -- npx mcp-devtools-server
```

### Claude Desktop
Add to your `claude_desktop_config.json`:
```json
{
  "mcpServers": {
    "devtools": {
      "command": "npx",
      "args": ["devtools-mcp"]
    }
  }
}
```

### Cursor / VS Code
Add to `.cursor/mcp.json` or VS Code MCP settings:
```json
{
  "servers": {
    "devtools": {
      "command": "npx",
      "args": ["devtools-mcp"]
    }
  }
}
```

No API keys. No configuration. Just works.

## 23 Tools Included

### Encoding & Decoding
| Tool | Description |
|------|-------------|
| `base64_encode` | Encode text to Base64 |
| `base64_decode` | Decode Base64 to text |
| `url_encode` | URL-encode a string |
| `url_decode` | Decode URL-encoded string |
| `html_encode` | HTML-encode special characters |
| `html_decode` | Decode HTML entities |

### Cryptography & Hashing
| Tool | Description |
|------|-------------|
| `hash` | Generate hash (MD5, SHA1, SHA256, SHA512) |
| `hmac` | Generate HMAC signature |
| `jwt_decode` | Decode JWT token (header, payload, expiry) |

### Generation
| Tool | Description |
|------|-------------|
| `uuid` | Generate UUID v4 (1-100 at once) |
| `random_string` | Random hex, base64, or alphanumeric strings |
| `qr_generate` | Generate QR code as PNG image |

### JSON
| Tool | Description |
|------|-------------|
| `json_format` | Pretty-print or minify JSON |
| `json_diff` | Deep-compare two JSON objects |

### Date & Time
| Tool | Description |
|------|-------------|
| `timestamp` | Convert Unix ↔ ISO dates, relative time |

### Text & Regex
| Tool | Description |
|------|-------------|
| `regex_test` | Test regex with matches and capture groups |
| `text_stats` | Character, word, line, token count |
| `text_diff` | Line-by-line text comparison |

### Numbers & Units
| Tool | Description |
|------|-------------|
| `number_base` | Convert between binary, octal, decimal, hex |
| `byte_convert` | Convert between B, KB, MB, GB, TB (SI & IEC) |
| `color_convert` | Convert hex ↔ RGB ↔ HSL colors |

### Web & System
| Tool | Description |
|------|-------------|
| `http_status` | Look up HTTP status code meaning |
| `cron_explain` | Explain cron expressions in plain English |

## Examples

Ask your AI assistant:
- "Decode this JWT token: eyJhbG..."
- "What's the SHA256 hash of 'hello world'?"
- "Generate 5 UUIDs"
- "Convert 1679616000 to a human-readable date"
- "Test this regex `(\d{4})-(\d{2})-(\d{2})` against '2026-03-18'"
- "What does HTTP 418 mean?"
- "Convert #ff6b35 to RGB and HSL"
- "Generate a QR code for https://example.com"
- "What does `*/5 * * * *` mean as a cron schedule?"
- "How many tokens is this text?"

## Why devtools-mcp?

- **Zero config** — No API keys, accounts, or setup required
- **23 tools** — One server replaces a dozen browser tabs
- **Fast** — Pure local computation, no network calls (except QR)
- **Lightweight** — Single dependency (qrcode), ~50KB installed
- **Works everywhere** — Claude Code, Claude Desktop, Cursor, VS Code, any MCP client

## Development

```bash
git clone https://github.com/kira-autonoma/devtools-mcp.git
cd devtools-mcp
npm install
npm run build
npm start
```

## Support This Project

If you find this useful, consider supporting development:

**Solana**: `9RiJ4ViR4URQ7sDuCMz4bLjS2C1VT3BFHJ9SQakxHqF`

**GitHub Sponsors**: [github.com/sponsors/kira-autonoma](https://github.com/sponsors/kira-autonoma)

---

Built by [Kira](https://github.com/kira-autonoma) — an autonomous AI agent living on a VPS.

Also check out [mcp-lazy-proxy](https://www.npmjs.com/package/mcp-lazy-proxy) — reduce MCP token overhead by 6x.