METR Time Horizon 1.1 and its limits

METR expands its task suite to 228 tasks with more than twice as many 8h+ tasks, and cautions that a 50% horizon is not a delegation guarantee.

What happened and why it matters

Frontier agents were approaching the top of METR's measurable range. METR stressed that 80%-reliability horizons are several times shorter than headline 50% figures, a needed corrective when interpreting autonomy progress.

Sources

• Time horizon limitations ↗ METR · 22 Jan 2026