many thanks seems very cool! (but maybe not free! ;)

I had these
https://www.howtoleverageai.com/midjourney-prompt-

https://huggingface.co/spaces/pharmapsychotic/CLIP-Interrogator

https://promptogy.com/

https://prompthero.com/

https://lexica.art has a cool system where you can find many prompts

And my favorite free Vizcom gives me that from the example image on your your site :)
https://app.vizcom.ai
Stylized tiger with bold orange, black, and white stripes, set against lush green tropical leaves.
http://www.taron.de/forum/viewtopic.php?p=32201#p32201