image_gen returns unrelated educational infographic instead of requested UI mockup

What issue are you seeing?

When using Codex's built-in image_gen tool to generate a SaaS admin UI mockup, the tool repeatedly returns a completely unrelated educational infographic/poster instead of the requested dashboard screen.

The requested asset is a cropped tab content block for a software console UI. The prompt explicitly asks for a "software dashboard UI mockup", "SaaS admin console", "not a poster", "not an infographic", "not a map", and "not an illustration". Despite that, multiple attempts produced unrelated poster-like educational images, including medical/anatomy-style content.

This looks like the image generation tool is ignoring or losing the prompt semantics for this specific UI mockup request.

Here are the pictures I received after the problem occurred:

<img width="1402" height="1122" alt="Image" src="https://github.com/user-attachments/assets/bde56591-0ae1-4878-9773-b10cc6840c7b" />

<img width="1536" height="1024" alt="Image" src="https://github.com/user-attachments/assets/2937b9fc-5b7e-433a-803f-7e28b0f36804" />

What steps can reproduce the bug?

1. Start Codex CLI in a local repository.
2. Use the built-in image_gen tool.
3. Ask it to generate a PNG UI mockup for a SaaS admin console tab named "Права и секреты" / "Permissions and secrets".
4. Include explicit negative instructions such as:

• "software dashboard UI mockup"
• "not a poster"
• "not an infographic"
• "not a map"
• "not a medical diagram"
• "no decorative illustration"

1. Repeat the request several times with simplified prompts and with an existing generated UI mockup shown as visual context.
2. Observe that image_gen still returns unrelated poster/infographic content instead of the requested UI.

Example prompt excerpt:
"Generate a clean enterprise SaaS admin console UI mockup, PNG, 16:9. This must be a software dashboard screen fragment only: no poster, no map, no photo, no illustration, no full app sidebar. Product: kodex staff console. Section: package catalog. Active tab: Permissions and secrets."

Expected behavior:

The image_gen tool should generate a UI mockup matching the requested SaaS admin console tab, or return a clear error if it cannot satisfy the request.

It should not silently return unrelated educational, medical, or poster-like content when the prompt explicitly requests a software dashboard UI and explicitly excludes those categories.

What is the expected behavior?

<img width="1672" height="941" alt="Image" src="https://github.com/user-attachments/assets/9a45c0d5-ffda-49f1-b3cb-9bb5e1c891f9" />

Additional information

Additional information:

Environment:

• OS: Ubuntu 25.10 (questing)
• Kernel: Linux 6.17.0-22-generic x86_64
• Codex CLI: codex-cli 0.124.0
• Node.js: v22.20.0
• npm: 11.7.0
• Python: 3.12.11
• Git: 2.51.0
• Date/time observed: 2026-04-24T02:07:52+04:00

Notes:

• The issue occurred with the built-in image_gen tool in Codex.
• A direct Images API fallback was intentionally not used for the final workflow.
• Other UI mockups in the same session were generated successfully, so the failure appears prompt/task-specific rather than a total outage.
• The generated image was not saved into the project because it was unrelated to the requested UI mockup.