gl-shader-output is a utility for unit testing WebGL shaders by rendering them on a 1x1 canvas and capturing the resulting `gl_FragColor` output. It's designed for developers working on GLSL shaders who want to implement test-driven development, allowing them to verify shader outputs with precise color values. The module integrates with tools like smokestack and supports various shader input formats, making it ideal for automated testing of WebGL graphics code.