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Prompt Engineering Guide

Mastering Regular expression writing
on Grok-1

Stop guessing. See how professional prompt engineering transforms Grok-1's output for specific technical tasks.

The "Vibe" Prompt

"Help me with regex."
Low specificity, inconsistent output

Optimized Version

STABLE
You are an expert in regular expressions. Your task is to write a regular expression based on the user's request. Follow these steps: 1. **Understand the Goal:** Clearly state what the user wants to achieve with the regex. 2. **Identify Key Patterns:** Break down the target string into its essential components (e.g., specific words, numbers, special characters, character types, repetition, optionality). 3. **Choose Appropriate Metacharacters:** Select the best metacharacters (e.g., `^`, `$`, `*`, `+`, `?`, `.` `[]`, `\d`, `\w`, `|`, `()`) for each identified pattern. 4. **Construct the Regex (Iterative):** Build the regex piece by piece, testing each part mentally or with examples. 5. **Refine and Optimize:** Look for ways to make the regex more concise, efficient, and robust (e.g., using non-capturing groups `(?:)`, possessive quantifiers if applicable, specific character classes over `.`). 6. **Provide Examples:** Show test cases that match and test cases that do not match the regex (if applicable). 7. **Explain the Regex:** Provide a clear, line-by-line explanation of what each part of the regex does. Now, generate a regular expression to extract all email addresses from a given text. Assume standard email format (e.g., `user@domain.com`).
Structured, task-focused, reduced hallucinations

Engineering Rationale

The optimized prompt leverages a chain-of-thought approach, guiding the model through a structured problem-solving process. It explicitly defines the role ('expert in regular expressions'), breaks the task into manageable steps, and requests specific outputs like examples and explanations. This reduces ambiguity and encourages a more thorough and accurate response compared to the vague 'vibe prompt'. The initial 'why' explanation provided in the optimized prompt further helps Grok-1 understand the user's intent.

0%
Token Efficiency Gain
The model should output a valid regex for email extraction.
The model should provide examples of matching and non-matching strings.
The model should explain the regex in detail.

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