operational metric

Experienced developer productivity

Randomized access to AI tools on real repository issues.

Observed R&D automation

What this measure tells us

Operational counterpoint to benchmark performance.

  • Experienced developers in familiar open-source repositories; not representative of all work.
  • Later study reports selection bias, so no unqualified trend.

Results by version

Late-2025 study update

2026-02-24

Selection effects prevent a reliable current effect estimate.

Metric definitions

Interpretability assessment (qualitative): A task-specific measurement; not a percentage of RSI achieved.

AI-assisted task-time change (percent): Negative means faster completion. Not a reliable population effect because of selection bias.

Published results · Late-2025 study update
KeySystem / organizationMetricReported resultDateProtocolVerificationEvidence
—METR10 returning and 47 newly recruited developersInterpretability assessmentMETR reports that selection effects make the later experiment unreliable for estimating current productivity gains.2026-02-24productivity-later-pindependent evaluation
—METRReturning original-study participantsAI-assisted task-time change-18%Confidence interval: -38% to +9% · Source-reported confidence interval; level not specified in summary2026-02-24productivity-returning-pindependent evaluation
—METRNewly recruited developersAI-assisted task-time change-4%Confidence interval: -15% to +9% · Source-reported confidence interval; level not specified in summary2026-02-24productivity-new-pindependent evaluation

Early-2025 randomized trial

2025-07-10 · 246 tasks

16 developers; issue-level randomization.

Metric definitions

Change in completion time (percent): A task-specific measurement; not a percentage of RSI achieved.

Published results · Early-2025 randomized trial
KeySystem / organizationMetricReported resultDateProtocolVerificationEvidence
—METR16 experienced open-source developersChange in completion time19% longer2025-07-10productivity-pindependent evaluation

Version lineage

Reference points

No reference points are indexed for this measure.

Availability

What is publicly available
ResourceStatus
public descriptionyes
public resultsyes
public tasksno
public codeunknown
public evaluation serviceunknown

Official sources