Codex Image Gen

Generate a real raster image from a text prompt when the running agent has no native image generator. The mechanism is non-obvious: the headless codex exec path genuinely calls the image tool, but it never writes the PNG to disk — only the Codex desktop app has the plumbing that polls the async job and saves it. The finished image is still recoverable, because its full base64 PNG is recorded in the session rollout JSONL. Run the prompt, read the session id Codex prints, open the matching rollout, and decode the largest result string to a PNG.

When this is the right tool

• The agent needs a generated raster image (icon, illustration, texture, app icon, placeholder art) and has no built-in image-generation tool.
• A codex CLI is installed and logged in, and shelling out to it is allowed.
• A vector result is not required — this produces a PNG, not an SVG.

If a native image tool exists, prefer it. If the deliverable is a logo or other crisp vector, prefer a vector workflow.