Spin up a background agent to do the research, so that you keep working while it reads.
Its job:
- Investigate the question against primary sources — official documentation, source code, specs, first-hand APIs — and not a secondary summary of them. Chase every claim back to the source that holds it.
- Write the findings into a single Markdown file, citing the source of each claim.
- Save it where the repo already keeps notes of this kind; follow the existing convention and, if there is none, put it in a sensible place and say where.