Nick Cammarata, who co-authored early mechanistic interpretability research at OpenAI, reversed his earlier pessimism about the field on October 15-16, saying that where primitive automated tools once found only around 2% of neurons legible, modern agentic tools show the vast majority of neurons in models up to trillions of parameters are legible and their circuits comprehensible.
He attributed the earlier pessimism partly to misunderstood cases that were not genuinely uninterpretable. Sam Altman responded positively to the announcement.