Howto codex

Howto codex · Reading edition

A complete reading path.

10 modules, 60 detailed lessons in English. Estimated practice time: 18h 39m.

Module 01 · beginner

Commands and your first session

Start in the right place, discover real commands and turn repeated requests into usable workflows.

6 lessons · 84 min estimated

  1. Open Codex and complete a first read-only task 14 min estimated
  2. Use built-in commands without guessing 14 min estimated
  3. Replace old custom commands with reusable skills 14 min estimated
  4. Use connected tools without inventing MCP commands 14 min estimated
  5. Create a small project skill 14 min estimated
  6. Choose the right control for the task 14 min estimated

Module 02 · beginner

Project guidance and memory

Keep durable instructions explicit and understand what local Codex memories can and cannot preserve.

5 lessons · 70 min estimated

  1. Separate instructions, chat context and memories 14 min estimated
  2. Initialize useful project guidance 14 min estimated
  3. Understand the AGENTS.md instruction chain 14 min estimated
  4. Split modular guidance from execution rules 14 min estimated
  5. Use local memories with provenance and limits 14 min estimated

Module 08 · beginner

Checkpoints, recovery and Git

Separate conversation history from file state, inspect changes and practise bounded recovery.

5 lessons · 70 min estimated

  1. Know what a checkpoint actually protects 14 min estimated
  2. Find the evidence needed for recovery 14 min estimated
  3. Choose between chat reset and file restoration 14 min estimated
  4. Experiment with branches, forks and small checks 14 min estimated
  5. Use Git checkpoints as durable file evidence 14 min estimated

Module 10 · beginner

Working from the command line

Use the interactive CLI and bounded scripted runs, with deliberate permissions and verifiable outputs.

5 lessons · 70 min estimated

  1. Understand the interactive CLI and scripted runs 14 min estimated
  2. Navigate the CLI command families 14 min estimated
  3. Set scope with deliberate CLI flags 14 min estimated
  4. Capture final answers and structured events 14 min estimated
  5. Choose high-value, bounded CLI tasks 14 min estimated

Module 03 · intermediate

Skills

Build reusable Codex workflows, control their activation and verify how they behave in delegated work.

6 lessons · 109 min estimated

  1. Choose the right job for a skill 15 min estimated
  2. Understand progressive disclosure 16 min estimated
  3. Create a project-scoped skill 20 min estimated
  4. Control when a skill is invoked 18 min estimated
  5. Use skills in delegated work 20 min estimated
  6. Maintain, disable and evaluate skills 20 min estimated

Module 05 · intermediate

MCP

Connect Codex to the right tools, separate configuration from authorization and recognize product-specific integration boundaries.

6 lessons · 117 min estimated

  1. Understand the MCP request path 17 min estimated
  2. Choose a transport and verify a connection 22 min estimated
  3. Separate configuration scope from access scope 20 min estimated
  4. Bring external resources into context accurately 19 min estimated
  5. Distinguish finding a tool from searching content 19 min estimated
  6. When Codex is the agent you want to embed 20 min estimated

Module 04 · intermediate

Subagents

Delegate bounded work, configure focused roles and combine evidence without confusing threads, permissions or filesystem isolation.

7 lessons · 141 min estimated

  1. Delegate independent work with a clear contract 18 min estimated
  2. Configure a narrow custom Codex agent 22 min estimated
  3. Use the actual Codex built-in roles 17 min estimated
  4. Chain agents through explicit evidence handoffs 20 min estimated
  5. Manage background work without losing its state 18 min estimated
  6. Separate agent threads from worktree isolation 23 min estimated
  7. Coordinate a small team without assuming a team mode 23 min estimated

Module 06 · intermediate

Hooks

Build and observe lifecycle hooks, inspect trust and wire contracts, then debug a bounded completion check.

7 lessons · 154 min estimated

  1. Hooks: a lifecycle, not a reminder 18 min estimated
  2. Configure hook sources deliberately 22 min estimated
  3. Choose a supported hook handler 20 min estimated
  4. Place checks at the right event 23 min estimated
  5. Understand hook input and output 24 min estimated
  6. Build a bounded Stop review instead of an unsupported prompt hook 24 min estimated
  7. Debug hooks as small integrations 23 min estimated

Module 09 · advanced

Advanced features

Plan and implement, compare reasoning, inspect permissions, run headless work and manage a real app schedule.

7 lessons · 159 min estimated

  1. Build an advanced workflow without losing control 20 min estimated
  2. Plan before consequential implementation 23 min estimated
  3. Tune reasoning with evidence 21 min estimated
  4. Understand automatic approval review 23 min estimated
  5. Create, inspect and stop a scheduled task 24 min estimated
  6. Read permission modes as effective boundaries 22 min estimated
  7. Run headless work with codex exec 26 min estimated

Module 07 · advanced

Plugins

Build, install and test a versioned plugin, then distribute it with verified update, rollback and removal steps.

6 lessons · 145 min estimated

  1. Plugins: reusable capability packages 20 min estimated
  2. Design the plugin around one user journey 23 min estimated
  3. Write the right plugin manifest 26 min estimated
  4. Understand directories and marketplace sources 22 min estimated
  5. Test the package, then the workflow 26 min estimated
  6. Release, update and remove a plugin 28 min estimated