{"id":"fe5bb033bf342fcf423a99a00073594a19d9970579816fd3801a4d0d33c9be2e","title":"METR clarifies what its time horizon measure can and cannot say","argument":"Originally published on January 22, 2026, this note from an unnamed METR researcher argues that time horizon is an imprecise measure of performance on particular tasks, not a measure of how long an AI can work independently. The author defines it as the amount of serial human labor an AI can replace at a 50% success rate, and stresses that estimates have wide error bars and vary sharply across task domains. The note also warns that benchmark tasks may not represent real-world work, and that a 50% success rate does not make a task suitable for delegation when reliability matters.\n\nThe author nevertheless stands by the paper’s central trend: a long-run doubling in time horizon every 6–7 months, and a linear extrapolation predicting a one-month time horizon in 2030. 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This matches the source, whose author identifies only as one of the main authors of the time horizon paper. The reading also carries the disclaimer that notes do not necessarily reflect METR's views, and it keeps assertions attributed to the author.","excerpt":"As one of the main authors, I often see various misinterpretations of our work."},{"dimension":"summary","status":"pass","explanation":"The summary faithfully conveys the author's position. Time horizon is serial human labor replaced at 50% success, with wide error bars and domain variation. The author warns about delegation and benchmark representativeness, still stands by the 6–7 month doubling trend and the 2030 extrapolation, and flags Tom Cunningham's baseline concern. Time horizon and benchmark are defined beside the reading. The question follows directly from the source's stated concern.","excerpt":"I still believe in the core results, I believe that many people to some extent both overstate the precision of our time horizon measurements"},{"dimension":"date","status":"pass","explanation":"The reading states January 22, 2026. This matches the UTC calendar day of originalPublished (2026-01-22T08:00Z) and the URL path. The 2030 one-month horizon is presented as a linear-extrapolation prediction, not an outcome. There is no hindsight framing, and the reading does not rely on later material.","excerpt":null},{"dimension":"support","status":"uncertain","explanation":"Most claims match their excerpts. One does not: the third claim says visual computer use time horizons were 40–100 times lower than for math. The source says math was fairly similar to the original software/research tasks, while visual computer use was 40–100x lower, which is a comparison against the original task domain rather than against math. Smallest repair: change the comparison to the original software and research tasks, noting that math was similar.","excerpt":"time horizons are fairly similar for math, but 40-100x lower for visual computer use tasks"},{"dimension":"media","status":"pass","explanation":"No media was selected and no verified media candidates were supplied, so there is nothing to mismatch.","excerpt":null}],"createdAt":"2026-11-09T00:55:53.408Z","model":"anthropic/claude-opus-5.5"}],"correctionUrl":"https://escapemeridian.com/corrections/"}