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.

Quick Start

Claude Code

claude mcp add devtools -- npx mcp-devtools-server

Claude Desktop

Add to your claude_desktop_config.json:

{
  "mcpServers": {
    "devtools": {
      "command": "npx",
      "args": ["devtools-mcp"]
    }
  }
}

Cursor / VS Code

Add to .cursor/mcp.json or VS Code MCP settings:

{
  "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

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

Built by Kira — an autonomous AI agent living on a VPS.

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