Guides

Writing AI Agent System Prompts and Rules Files: A Practical Guide

The system prompt is the most important input you give an AI agent — it defines identity, constraints, output format, and failure behaviour. This guide covers how to write system prompts and agent rules files that produce consistent, reliable behaviour.

API Response Testing: Writing Effective Assertions for REST APIs

Flaky API tests almost always fail because of weak assertions. This guide covers how to write assertion strategies that catch real regressions without breaking on irrelevant changes — including type checking, schema validation, and the patterns that catch real bugs.

Color Palette Generation for Web Projects: Theory and Practice

A practical guide to building color palettes that work — covering color models, harmony rules, accessibility contrast, dark mode, and the tools that generate production-ready palettes from a single starting color.

CSS Selectors: The Complete Guide for Frontend Developers

A practical reference to every CSS selector — from basic type and class selectors to pseudo-elements, combinators, and the :has() parent selector. Includes specificity rules, performance notes, and real-world patterns.

Data Storage Units Explained: Bits, Bytes, Megabytes, and the SI vs IEC Confusion

1 GB can mean 1 000 000 000 bytes or 1 073 741 824 bytes depending on who is writing the spec. This guide explains why, covers all storage and transfer rate units, and helps you convert correctly between them.

How to Generate and Sign JWTs: A Practical Developer Guide

Step-by-step guide to creating JSON Web Tokens from scratch — choosing the right algorithm, signing securely, setting claims correctly, and avoiding the implementation mistakes that leak data or break authentication.

HTML Entities Explained: When and How to Escape Characters

HTML entities prevent broken layouts and security vulnerabilities. This guide covers named and numeric entities, when escaping is mandatory, and the characters developers forget most often.

HTML Formatting and Beautification: Clean Markup for Maintainable Code

Unformatted HTML is hard to review, hard to debug, and hard to maintain. This guide covers HTML formatting conventions, when to beautify vs. minify, the tools that automate both, and the patterns that keep markup readable as a project grows.

JSON and CSV: Converting Between Formats for Analysis and Import

JSON and CSV serve different purposes — and converting between them correctly requires handling nested objects, arrays, special characters, and encoding. This guide covers the conversion mechanics, common failure points, and the tools that handle edge cases automatically.