I Built 44 MCP Developer Tools — Here Are the 10 That Save Me the Most Time

Source: Dev.to

The Setup (30 seconds)

npm install -g mcp-devutils

Add to your Claude Desktop config (claude_desktop_config.json):

{
  "mcpServers": {
    "devutils": {
      "command": "mcp-devutils"
    }
  }
}

That’s it. Fifteen tools are free immediately; the remaining 29 unlock with a $5 Pro key.

Free Tools I Use Every Day

1. UUID Generator

Instead of opening a browser tab, just ask Claude: “Generate 5 UUIDs.” Done.

2. JWT Decode

Paste a JWT token into the chat and ask Claude to decode it. No more jwt.io tabs; you get the header, payload, and expiry instantly.

3. Hash & HMAC

Need a SHA‑256 hash of a string? HMAC for an API signature? Just ask. Supports MD5, SHA‑1, SHA‑256, SHA‑512.

4. Base64 Encode/Decode

Encode/decode base64 strings multiple times a day without leaving your editor context.

5. Timestamp Converter

Convert between Unix timestamps and human‑readable dates.
“What’s 1711234567 in UTC?” — answered right in the chat where you’re debugging.

6. Cron Explainer

Paste a cron expression (e.g., 0 */4 * * *) and get a plain‑English explanation of its schedule.

Pro Tools That Changed My Workflow

7. JSON Diff (Pro)

Compare two JSON objects and see exactly what changed—additions, deletions, modifications. Handy for debugging API responses that “should be the same but aren’t.”

8. AES Encrypt/Decrypt (Pro)

Encrypt sensitive strings without leaving your editor. Useful for config values before committing.

9. JWT Create (Pro)

Create JWTs with custom payloads and secrets, not just decode them. Essential for testing auth flows.

10. CSV/JSON Convert (Pro)

Drop a CSV into the chat and get clean JSON back, or vice versa. Saves you from writing throwaway scripts.

The Full Tool List

15 Free tools:

• UUID
• Hash
• HMAC
• Base64
• Timestamp
• JWT Decode
• URL Encode/Decode
• JSON Format
• Regex Test
• Cron Explain
• Color Convert
• HTTP Status
• Slugify
• HTML Escape
• Random String

29 Pro tools ($5 one‑time):

• Nanoid
• Hex Encode
• JWT Create
• JSON Diff
• JSON Query
• CSV/JSON Convert
• Regex Replace
• Semver Compare
• Chmod Calc
• Text Diff
• Number Base
• Lorem Ipsum
• Word Count
• Byte Count
• CIDR Calc
• Case Convert
• Markdown TOC
• Env Parser
• IP Info
• Password Strength
• Data Size
• String Escape
• Char Info
• SQL Format
• Epoch Convert
• AES Encrypt/Decrypt
• RSA Keygen
• Scrypt Hash

Get It

npm install -g mcp-devutils

• GitHub: hlteoh37/mcp-devutils
• Unlock Pro ($5): Buy a Pro key — supports indie development and unlocks all 29 Pro tools
• npm: 250+ weekly downloads

If you find it useful, a star on GitHub helps others discover it.

What developer utilities do you wish you had as MCP tools? Drop a comment — I might build it next.