Automatic alt text on upload

With Automatic Generation on, every image you upload gets AI alt text a few moments later, as long as its Alternative Text is empty. Images already in your library aren't touched. For those, see Generate missing alt text.

Save a site API key first

Automatic alt text needs an OpenRouter key saved for the whole site. A key pasted on the AI Alt Text screen isn't enough.

1. Go to Dirigible → AI / OpenRouter.
2. Fill in OpenRouter API Key and save.
3. Go back to Dirigible → AI Alt Text.

Until a site key is saved, the automatic section asks you to add one, and the checkbox doesn't appear.

Turn it on

1. Open Dirigible → AI Alt Text.
2. Under Automatic Generation, check Automatically generate alt text when images are uploaded.
3. Change the Model if you want. The recommended default works well.
4. Upload a test image in Media → Library and check that Alternative Text fills in after a short wait.

Uncheck the box to turn it off. It never overwrites alt text you've already written.

If the AI can't describe an image

Sometimes the AI replies with an error message, such as "I'm unable to see the image", instead of a description. That's never saved. Dirigible AI tries the image again a few hours later, then a day after that. After three failed tries it marks the image Skipped in Media → Library and on the AI Alt Text screen, and stops trying. Write its alt text yourself or use Generate Alt Text with another model.

Retries are spread out and capped at 20 images a day, so a backlog doesn't use up your OpenRouter credits all at once.

Tips

• Each upload uses OpenRouter credits.
• Uploading a large batch queues a lot of work in the background. To watch progress instead, turn automatic generation off, upload the batch, then use Generate All Alt Text on the AI Alt Text screen.