regex-vs-llm-structured-text

Installation
SKILL.md

Regex vs LLM for Structured Text Parsing

A practical decision framework for parsing structured text (quizzes, forms, invoices, documents). The key insight: regex handles 95-98% of cases cheaply and deterministically. Reserve expensive LLM calls for the remaining edge cases.

When to Activate

  • Parsing structured text with repeating patterns (questions, forms, tables)
  • Deciding between regex and LLM for text extraction
  • Building hybrid pipelines that combine both approaches
  • Optimizing cost/accuracy tradeoffs in text processing

Decision Framework

Is the text format consistent and repeating?
├── Yes (>90% follows a pattern) → Start with Regex
│   ├── Regex handles 95%+ → Done, no LLM needed
│   └── Regex handles <95% → Add LLM for edge cases only
└── No (free-form, highly variable) → Use LLM directly
Related skills
Installs
2
GitHub Stars
1
First Seen
Mar 4, 2026