A local toolkit that surfaces 23 common developer utilities through MCP tools like base64_encode, jwt_decode, uuid, hash, regex_test, and timestamp. No network calls except for QR code generation, no API keys, no configuration file needed. Reach for this when you're mid-conversation with Claude and need to decode a JWT, generate a few UUIDs, test a regex pattern, convert Unix timestamps, or look up what HTTP 418 means without breaking focus to open browser tabs. Also includes JSON diffing, cron expression parsing, color conversion between hex/RGB/HSL, and byte unit conversion. Pure local computation keeps it fast and private.
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.
claude mcp add devtools -- npx mcp-devtools-server
Add to your claude_desktop_config.json:
{
"mcpServers": {
"devtools": {
"command": "npx",
"args": ["devtools-mcp"]
}
}
}
Add to .cursor/mcp.json or VS Code MCP settings:
{
"servers": {
"devtools": {
"command": "npx",
"args": ["devtools-mcp"]
}
}
}
No API keys. No configuration. Just works.
| 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 |
| Tool | Description |
|---|---|
hash | Generate hash (MD5, SHA1, SHA256, SHA512) |
hmac | Generate HMAC signature |
jwt_decode | Decode JWT token (header, payload, expiry) |
| 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 |
| Tool | Description |
|---|---|
json_format | Pretty-print or minify JSON |
json_diff | Deep-compare two JSON objects |
| Tool | Description |
|---|---|
timestamp | Convert Unix ↔ ISO dates, relative time |
| 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 |
| 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 |
| Tool | Description |
|---|---|
http_status | Look up HTTP status code meaning |
cron_explain | Explain cron expressions in plain English |
Ask your AI assistant:
(\d{4})-(\d{2})-(\d{2}) against '2026-03-18'"*/5 * * * * mean as a cron schedule?"git clone https://github.com/kira-autonoma/devtools-mcp.git
cd devtools-mcp
npm install
npm run build
npm start
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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