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Every module in one place

A hands-on course that gets you fluent in the frontier-model coding tools developers actually use in the terminal — Claude Code (Anthropic), OpenAI Codex, and the Google Gemini CLI — taught side by side, so you learn the concepts once and the commands for each.

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Resume

Free — fundamentals & overviews

Core Concepts

Prompts, skills, the context window, tokens, and how to think about picking a model.

Getting Started

Installing Claude Code and running it for the first time.

Claude Clients

What Claude.ai, Claude Desktop, and Claude Code each do best, and when to reach for each one.

Slash Commands & Skills

Built-in commands, custom commands, and packaged skills that extend what Claude Code can do.

Writing Effective Prompts

How to give Claude Code the context and structure it needs to get things right the first time.

Agentic Workflows & Subagents

Multi-step, tool-using workflows and how subagents help break down larger tasks.

Try It: Playground

Type a prompt and see illustrative, scripted responses from Claude.ai, Claude Desktop, and Claude Code side by side.

Choosing a Frontier Model

A provider-neutral guide to picking among Claude, OpenAI/GPT, and Gemini — reasoning, speed, cost, context, and ecosystem, with a decision table.

OpenAI for Coding — Overview

The OpenAI coding surfaces — the agentic Codex CLI, the cloud, and the API — when to use each, and how they map onto Claude Code.

Google Gemini for Coding — Overview

The Gemini CLI, the Gemini API, and AI Studio — when to use each, the generous free tier, and how it compares to Claude Code and Codex.

Premium — advanced track & deep-dives

Claude Code Cheatsheet

A searchable quick reference for every Claude Code command — CLI commands and flags, /slash commands, bundled skills, and shortcuts.

Advanced: Skills in Depth

SKILL.md anatomy, progressive disclosure, writing descriptions that auto-trigger, and invocation control.

Advanced: Loops & Goals

Drive bounded autonomy with /loop and /goal — fixed-interval vs self-paced runs, and avoiding runaway cost.

Advanced: Workflows & Multi-Agent

Subagents via /agents, background and parallel agents, orchestration patterns, and when multi-agent beats a single agent.

Advanced: Automation, MCP & Hooks

Headless claude -p for CI, scheduled cron routines, plan mode, MCP servers, and settings.json hooks.

Advanced: Context Mastery

CLAUDE.md memory scopes, output styles, checkpointing and /rewind, permission modes, and context hygiene.

OpenAI Codex CLI in Depth

Install & auth, codex exec, slash commands, approval & sandbox modes, AGENTS.md, MCP, and Codex cloud.

Gemini CLI in Depth

Install/channels, auth options, interactive vs -p, flags, slash commands, GEMINI.md, MCP, and model selection.

Prompting Across Frontier Models

Portable prompt patterns, the instruction-file equivalents (CLAUDE.md / AGENTS.md / GEMINI.md), and multi-model pipelines.