Regex Lab Mcp

io.github.ryudi84Published by GitHub account ryudi84v1.0.2Updated Oct 27, 2026

Test, explain, and generate regular expressions

VerifiedSTDIODesktop onlyDeveloper ToolsData & Analytics

Overview

AI-generated overview

A local MCP server that lets an AI assistant test, replace with, and validate regular expressions without leaving the IDE.

What you can do
  • Test a regex pattern against a string and get all matches with positions and capture groups
  • Replace matches in a string using a pattern and replacement string
  • Check whether a regex pattern is syntactically valid
When to use it
Useful when you are writing or debugging regular expressions and want the assistant to try patterns against sample text, preview replacements, or confirm a pattern compiles, instead of switching to a browser-based regex tester.
Requirements
Runs as a local process over stdio, started with npx regex-lab-mcp (Node.js required). No authentication, environment variables or headers are declared. Desktop-only; not available as a web executable.
Before you install
The README's example uses a tool name that differs from the documented tool list, so verify the actual tool names after connecting. Text you pass to the tools is sent to the local server process; no third-party data transfer is described.

Installation

In SourceWeft

  1. Open Regex Lab Mcp in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Desktop only via STDIO. STDIO servers start a local process, so they need the SourceWeft desktop host.

Other MCP clients

Follow the launch instructions in the repository.

README

regex-lab-mcp

[npm version] [npm downloads] [License: MIT] [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

bash
npx regex-lab-mcp

Claude Desktop / Cursor / Windsurf

Add to your MCP configuration:

json
{  "mcpServers": {    "regex-lab": {      "command": "npx",      "args": ["-y", "regex-lab-mcp"]    }  }}

Tools (3)

ToolDescription
test_regexTest a regex pattern against a string. Returns all matches with positions and capture groups.
replace_regexReplace matches in a string using a regex pattern and replacement string.
validate_regexCheck if a regex pattern is syntactically valid.

Examples

Test pattern:

json
{  "tool": "regex_test",  "arguments": {"pattern": "\\d{3}-\\d{4}", "text": "Call 555-1234"}}

Build from Source

bash
git clone https://github.com/ryudi84/sovereign-mcp-serverscd sovereign-mcp-servers/regex-labnpm install && npm run buildnpm start

Part of the Sovereign MCP Suite

This is one of 34 MCP servers with 121 tools built by Sovereign.

CategoryServers
Web & SEOweb-scraper, seo-analyzer, meta-forge
Developer Toolsgithub-stats, code-quality, api-tester, api-forge
Data & Encodingjson-forge, base64-forge, hash-forge, regex-lab
Generatorsuuid-forge, password-forge, lorem-forge, landing-forge
DevOpsenv-forge, cron-forge, ip-calc, diff-forge
Frontendcolor-forge, gradient-forge, shadow-forge
Contentmarkdown-forge, readme-forge, changelog-forge
Metamcp-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!

Source: regex-lab/README.md at commit da6bbcc

Tools

0
SourceWeft has not started this package in its sandbox yet, so its tools are not known.

Version history

1
  1. v1.0.2LatestSep 16, 2026

Score

40% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 days25 pts

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  • Auth declared10 pts

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  • Tools listed15 pts

    Answer tools/list without a credential, or ship a package that starts in a sandbox without one.

  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts
  • License10 pts

    Declare a license in the repository or the registry entry.