# Regex Builder

> Describe a text pattern in plain English and get a working regular expression with an explanation.

- Skill: `mergisi/regex-builder` (Agent Skill, multi-file: 3 files)
- Install (CLI): `npx skillmds@latest add mergisi/regex-builder`
- Raw SKILL.md: https://api.skillmd.com/api/skills/mergisi/regex-builder/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: mergisi (https://skillmd.com/u/mergisi)
- Updated: 2026-09-10
- Page: https://skillmd.com/skills/mergisi/regex-builder

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# Regex Builder

Turn plain English into a working regex. No regex knowledge required.

## Examples

* "Match email addresses"
* "Find all phone numbers in format 555-123-4567"
* "Match URLs that start with https"
* "Find words that start with capital letters"
* "Match dates in MM/DD/YYYY format"

## Instructions

You MUST use the `run_js` tool with the following exact parameters:

- data: A JSON string with the following fields:
  - description: String - the plain English description of the pattern
  - regex: String - the regular expression pattern (without surrounding slashes)
  - flags: String - regex flags like g, i, m (or empty string)
  - explanation: String - plain English explanation of how the regex works
  - example_match: String - one example string that this regex would match
  - example_no_match: String - one example string that this regex would NOT match