Regex Smith /regex-smith

About this skill

Regex Smith does two jobs: it writes regexes from plain-English descriptions ('match a US phone number, optional country code'), and it explains existing patterns in human terms — finally, an answer to the 40-character incantation in your codebase.

Every generated pattern ships with a test suite: positive cases it must match, negative cases it must reject, and edge cases around the boundaries. If the pattern can't pass its own tests, it doesn't ship.

It also flags catastrophic-backtracking risks before they hit production, which has quietly saved more than a few on-call rotations. Supports PCRE, JavaScript, Python, Go, and Rust flavors.

Inputs

• description · string
  Plain-English description of what to match.
• flavor · string
  pcre | javascript | python | go | rust. Default: pcre.
• test_cases · array
  Optional strings that must match / must not match.

Outputs

• pattern · string
  The generated regular expression.
• explanation · string
  Step-by-step breakdown of the pattern.
• tests · array
  Generated test cases with pass/fail results.

Permissions

Deny-by-default: the skill can only use what it declares.

Manifest

{
  "spec": "agentskills.io/v1",
  "name": "regex-smith",
  "version": "1.3.2",
  "description": "Generates regular expressions from plain-English descriptions, explains existing patterns step by step, and proves them against test cases.",
  "inputs": {
    "description": {"type": "string", "description": "Plain-English description of what to match.", "required": true},
    "flavor": {"type": "string", "description": "pcre | javascript | python | go | rust. Default: pcre.", "required": false},
    "test_cases": {"type": "array", "description": "Optional strings that must match / must not match.", "required": false}
  },
  "outputs": {
    "pattern": {"type": "string", "description": "The generated regular expression."},
    "explanation": {"type": "string", "description": "Step-by-step breakdown of the pattern."},
    "tests": {"type": "array", "description": "Generated test cases with pass/fail results."}
  },
  "permissions": ["exec:shell"],
  "author": "Patchline Labs",
  "category": "Development"
}

Changelog