codex-imagegen

Codex Imagegen

Overview

Invoke Codex CLI's built-in $imagegen skill to generate images with gpt-image-2. Translate the request into a concrete art direction, run the bundled safe launcher, move or post-process only a validated generated PNG, and visually verify the final asset.

Prerequisites:

• codex CLI v0.149 or newer, installed and logged in with codex login
• macOS or Linux
• Python 3.9 or newer, available as python3

Prompt flow

The Codex agent rewrites prompts into a labeled schema before calling gpt-image-2. A detailed prompt is normalized; a vague prompt is augmented with the agent's own choices. Fill every relevant slot to keep control:

$imagegen
Use case: <slug>
Asset type: <where the asset will be used, final size/aspect>
Primary request: <main ask in one sentence>
Input images: <Image 1: role; Image 2: role>          (only for edits/references)
Scene/backdrop: <environment, time, mood>
Subject: <main subject; for people: crop, pose, gaze, hands, expression>
Style/medium: <photo, illustration, 3D, print process>
Composition/framing: <viewpoint, placement, negative space, hierarchy>
Lighting/mood: <source, direction, temperature>
Color palette: <3-5 named colors or relationships>
Materials/textures: <surface details, grain, imperfections>
Text (verbatim): "<exact copy>"                        (omit if no text)
Constraints: <must keep, must render exactly once, must not change>
Avoid: <watermark, logo, extra text, unwanted styles>

Generate use-case slugs: photorealistic-natural, product-mockup, ui-mockup, infographic-diagram, scientific-educational, ads-marketing, productivity-visual, logo-brand, illustration-story, stylized-concept, historical-scene.

Edit use-case slugs: text-localization, identity-preserve, precise-object-edit, lighting-weather, background-extraction, style-transfer, compositing, sketch-to-render.

For detailed prompting guidance, read references/prompting-guide.md.