The Web Platform Tests project hosts essentially all the tests for web platform specs maintained by the W3C, WHATWG, and a few other standards orgs.

Specs written with the Bikeshed tool can indicate which WPT folders are associated with their specs, and then insert inline annotations detailing exactly which tests are relevant to the nearby text, which allows the spec to show those tests inline near the text they're testing, list test-pass stats, etc.

However, it's fairly annoying to do that inline annotation. You have to read each test to understand what it's testing, then you need to find where in the spec it should be inserted. While not difficult, this can take a few minutes per test, and it feels like shitwork. Until you do so, tho, Bikeshed continually complains about all the un-annotated tests it knows about.

This repository contains an LLM skill (following the Agent Skills model) which automates the insertion of WPT tests for a given spec. While in a spec folder, you can ask the agent to "insert missing tests", and it will use a local Bikeshed install to find the missing tests, then read both the spec and the tests to determine where best to insert them. It should only edit the .bs spec source file, and do nothing else permanent.

After running, manually verify that the tests all look like they're in a good spot with git diff.

(Still under development, but in local usage with Gemini it does quite well. I've even had it identify tests meant for a different level of the current spec, and correctly insert them into a <wpt hidden> element at the end of the doc.)