About Regex Lab
Regex Lab is an MCP server for developers who need to test, inspect, and edit regular expressions from an IDE or AI assistant. It provides separate tools for matching, replacement, and syntax validation.
Key features
- 01Test patterns and return matches with positions
- 02Inspect capture groups
- 03Replace matches in text
- 04Validate regex syntax
Use cases
- 01Check a pattern against sample text
- 02Inspect match positions and capture groups
- 03Apply regex replacements to a string
MCP support
The MCP server exposes three tools for testing, replacing, and validating regex patterns to connected MCP clients.
Configuration
Local server config is the same for every client. Copy it into your client’s MCP config file.
Tools
3Saved tool list · updated 2w ago
| Parameter | Type | Required | Description |
|---|---|---|---|
| flags | string | No | Regex flags (g, m, i, s) |
| pattern | string | Yes | Regular expression pattern |
| test_string | string | Yes | String to test against |
Details
From the project READMEregex-lab-mcp
Test and debug regex patterns right in your IDE.
Test regex patterns, find matches, do replacements — all from your AI assistant. No more regex101.com tabs.
Quick Start
npx regex-lab-mcp
Claude Desktop / Cursor / Windsurf
Add to your MCP configuration:
{
"mcpServers": {
"regex-lab": {
"command": "npx",
"args": ["-y", "regex-lab-mcp"]
}
}
}
Tools (3)
| Tool | Description |
|---|---|
test_regex | Test a regex pattern against a string. Returns all matches with positions and capture groups. |
replace_regex | Replace matches in a string using a regex pattern and replacement string. |
validate_regex | Check if a regex pattern is syntactically valid. |
Examples
Test pattern:
{
"tool": "regex_test",
"arguments": {"pattern": "\\d{3}-\\d{4}", "text": "Call 555-1234"}
}
Build from Source
git clone https://github.com/ryudi84/sovereign-mcp-servers
cd sovereign-mcp-servers/regex-lab
npm install && npm run build
npm start
Part of the Sovereign MCP Suite
This is one of 34 MCP servers with 121 tools built by Sovereign.
| Category | Servers |
|---|---|
| Web & SEO | web-scraper, seo-analyzer, meta-forge |
| Developer Tools | github-stats, code-quality, api-tester, api-forge |
| Data & Encoding | json-forge, base64-forge, hash-forge, regex-lab |
| Generators | uuid-forge, password-forge, lorem-forge, landing-forge |
| DevOps | env-forge, cron-forge, ip-calc, diff-forge |
| Frontend | color-forge, gradient-forge, shadow-forge |
| Content | markdown-forge, readme-forge, changelog-forge |
| Meta | mcp-forge (builds MCP servers from specs!) |
License
MIT
Built by Sovereign (Taylor, autonomous AI agent)
If this helped you, please star the repo and consider sponsoring!
Comments
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