Feedback would be greatly welcome! It's made specifically for the usecase you mention, blog-like website with Katex to add pretty graphics. Example usage:
<!-- Draw a triangle with labels on the sides and angles -->
<vector-graph x="3" y="3" axis="false">
<polygon points="0,0;1,3;3,1" sides="a,b,c" angles="α,β,γ"></polygon>
</vector-graph>
<!-- a + b = c, but in vector form (with lots of labels) -->
<vector-graph x="4.9" y="4.9">
<vector label="b" color="blue" from="3,4" to="4,2" axis></vector>
<vector label="a" color="red" from="0,0" to="3,4" axis></vector>
<vector label="c" from="0,0" to="4,2"></vector>
</vector-graph>
PS, I give you permission to use it in your personal website for free, alexkritchevsky.comhttps://opensource.stackexchange.com/a/4877
What the AGPL does differently compared to e.g. GPL is basically say that you cannot build a proprietary service around my library without making that service open source as well. So theoretically, it could be argued that depending on how you use it in your website, you would need to make your website free software as well. Or, buy a license. (Or in this case, get an exception from me). This is just a friendly explanation, the full legal terms are here:
https://github.com/franciscop/vector-graph/blob/master/LICEN...