First fire pit... is this safe?

So, there's an old fire pit way in the back of my property in an overgrown area. It's kinda like this one in the still frame for this video, with thin blocks and big wide blocks: https://www.homedepot.com/c/ah/how-to-build-a-fire-pit/9ba683603be9fa5395fab909c7f8239

It's only about a foot high, maybe three feet wide.

I mowed the area around it and tried to arrange the blocks so there are no air gaps in the wall, but I didn't do a great job on that front. And the grass is growing right up to the edge of the wall.

This doesn't seem safe to me (gaps in the wall of the pit, surrounded by nice flammable grass) but maybe I'm overthinking it?