Most public LLM evaluation measures what a model can do. Bommasani's Foundation Model Transparency Index, run out of Stanford CRFM, runs along a perpendicular axis: how much we know about the model itself — what was in its training data, which internal evaluations were performed, which downstream impacts have been documented, what has been disclosed publicly versus kept private. The underlying argument is direct: capability benchmarks mean little when the conditions that produced those capabilities are not on the record, and treating transparency as a separate research discipline (rather than a PR concern) is the only way the comparison gets honest.

Worth following when
you need to explain to an investor or partner why "this model has good benchmark scores" and "this model is transparent" are not the same answer.
Topics
Foundation Model Transparency Index methodology; what model documentation should contain; the gap between what model labs say and what they make verifiable.
Key works
Foundation Model Transparency Index (2023, ongoing, lead); "On the Opportunities and Risks of Foundation Models" report (2021, co-author); Stanford CRFM policy publications.