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The autonomy horizon exceeds what the measuring suite can gauge

development2026-05-09

Claim

METR reported an early Claude Mythos Preview hitting a fifty percent autonomy horizon of at least sixteen hours, the upper edge of what its suite can measure, with a doubling time of 103 days implying frontier autonomy reaches full range by November.

Reported metric: ≥16 h / 103-day doubling

Reporting date: 2026-05-09 (not necessarily the event date)

Sources

Attribution and reporting linked by this record; links do not imply independent verification.

Welcome to May 9, 2026 (theinnermostloop.substack.com)

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Welcome to May 9, 2026

Actor

Evidence for

Supersedes

The measured autonomy horizon reaches a full working week

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Citation formatCitation text

The autonomy horizon exceeds what the measuring suite can gauge
Innermost Loop KB — secondary record
Reporting date: 2026-05-09
KB permalink: https://nicholsn.github.io/innermost-loop-kb/developments/2026-05-09-a-sixteen-hour-horizon-at-the-edge-of-the-ruler
Claim: METR reported an early Claude Mythos Preview hitting a fifty percent autonomy horizon of at least sixteen hours, the upper edge of what its suite can measure, with a doubling time of 103 days implying frontier autonomy reaches full range by November.
Attributed sources:
- Welcome to May 9, 2026 — https://theinnermostloop.substack.com/p/welcome-to-may-9-2026
This citation does not imply independent verification of linked-source claims.

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