Wren Labs · ResearchUpdated monthly

Field Notes

Dated notes on how Wren behaves, measured. Every claim carries a number — and at least one number flatters nobody.

Field Notes

Ongoing notes on Wren's product behavior — how a specific surface actually performs under a repeatable test. Published when we have something worth measuring, not on a clock. Claim, method, data, limitations.

The Wren Index

A recurring monthly report. One citable page that rolls up the month's eval trend across every suite we track — summary faithfulness, instruction-following, Frames render, refusal calibration — with month-over-month numbers and a plain narrative.

Jul 20, 2026 Index

The Wren Index — July 2026

Month-over-month across every suite we track. Faithfulness held, instruction-following ticked up, refusal calibration slipped — and here's why.

Jul 18, 2026 Field Notes

How often do Frames actually render?

200 build prompts, one metric that matters: does the thing show up on screen. 96% valid HTML — and a clear look at the 4% that break.

Jul 11, 2026 Field Notes

Refusal calibration: when Wren says no

A small red/green suite of should-answer and should-refuse prompts. 71% correct — the least flattering number we publish, and the most useful.

See the live numbers on the public evals page, or read the method behind them in How we run honest evals.