[xVedun]

Maybe the only way to be sure is to have it generate (not stable diffuse) an image with the value in there.

[BugsJustFindMe]

You cannot know that anything it shows you was generated by executing the code and isn't merely a simulacrum of execution output. That includes images.

[Sophira]

Yes, you can. In my experience, models do not tend to write their own HTML output. They tend to output something like Markdown, or a modified version of it, and they wouldn't be able to write their own HTML that the browser would parse as such.