These docs are an attempt to help explain some of the helper function used in the articles on webgl2fundamentals.org.
The main ones are in webgl-utils.js and basically include
just 2 commonly used functions. One is webglUtils.createProgramsFromScripts. How it works
is described here. The other common function is
webglUtils.resizeCanvasToDisplaySize which is described in this lesson.
There's also another library in a few examples called TWGL. You can find that library and its documentation here.
If you're using WebGL to do 2D or 3D you'll likely need many math helper functions in JavaScript as well.
Functions for 2D math are here.
Functions for 3D math are here.
These docs are generated with JSDoc3. I find them very confusing to look at and in some places frustratingly verbose. If you have any experience with JSDoc3 and know how to make the docs more approachable and useful please submit a pull request or file an issue with details.