Showing Your Judgment When You Use AI Coding Tools

Give a reviewer a small project they can run and a decision they can inspect. An AI coding assistant may help write the first version; your portfolio should show how you turned that version into a defined, tested result.

Here is a compact exercise: turn a location record into a display label without inventing missing information. It is deliberately small enough to explain during an interview. Use synthetic inputs throughout.

Start with a miniature README

Create a file named README.md beside the implementation. Replace the bracketed notes with facts about your project:

Project: Location label
Reader: Someone reviewing an address before publication
Input: An object with non-empty city and country strings
Output: A trimmed "city, country" label
Failure: Missing, blank or incorrectly typed fields raise an error
Run: node demo.mjs
My contribution: [the decisions and code I wrote or revised]
Assistant contribution: [the suggestions I used and checked]
Known limit: Formats supplied text; does not verify a real location

The last line defines what the program does. A formatted label should never be presented as a successful geographic lookup.

Make the input and output repeatable

Save this example as demo.mjs. It uses built-in JavaScript features and makes no network request:

function locationLabel(input) {
  if (!input || Array.isArray(input) || typeof input !== 'object') {
    throw new Error('Expected a location object');
  }
  const fields = ['city', 'country'];
  for (const field of fields) {
    if (typeof input[field] !== 'string' || !input[field].trim()) {
      throw new Error(`Missing or invalid ${field}`);
    }
  }
  return `${input.city.trim()}, ${input.country.trim()}`;
}

console.log(locationLabel({ city: ' Aqaba ', country: 'Jordan' }));
// Expected output: Aqaba, Jordan

try {
  locationLabel({ city: 'Aqaba', country: '' });
} catch (error) {
  console.log(error.message);
  // Expected output: Missing or invalid country
}

Add a small test table to the README and record what your version actually produced:

Input	Expected result	What it tests
City with surrounding spaces	Trimmed display label	Formatting rule
Blank country	Clear error	Missing information
A list instead of an object	Clear error	Input shape
An unknown city string	That supplied string remains	No invented lookup or correction

Explain a revision, not just the final file

Imagine an initial version used String(input.country). A missing value could become visible text instead of producing an error. Keep that failing input, explain why you changed the rule, and show the new result. If an assistant suggested the repair, describe how you reviewed it.

For a real application, choose an example connected to the role's requirements. Include the exact run command, a short error case and the part you personally changed. A reviewer can then discuss your judgment using a concrete artifact rather than guessing from a screenshot or a list of tools.