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Published equation contexts

T50(t)  =  T0⋅2 (t−t0)/τ,τ≈7 monthsT_{50}(t) \;=\; T_0 \cdot 2^{\,(t - t_0)/\tau}, \qquad \tau \approx 7 \text{ months}

Why this formula appears here

A second, independently run measurement effort took a different approach: instead of asking whether an agent could solve one fixed set of tasks, it asked how long a task an agent could complete autonomously with 50% reliability, using human professional completion time as the unit. METR’s March 2025 study, compiled from 170 tasks and more than 800 human timing baselines across software engineering, cybersecurity and general reasoning work, reported that this “50%-task-completion time horizon” for frontier agents had been doubling approximately every seven months for six years running, and that the finding was robust to an order-of-magnitude error in the underlying measurements, which would…

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T50T_{50}

Symbol T_50

the length of task, measured in human-hours, that a frontier agent could complete autonomously with 50% reliability at time t.

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Published contexts (1)

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T50(t)  =  T0⋅2 (t−t0)/τ,τ≈7 months,T_{50}(t) \;=\; T_0 \cdot 2^{\,(t - t_0)/\tau}, \qquad \tau \approx 7 \text{ months},

Equation 1 · AI Agents & Systems

From Origins to Frontier: A History of Claude Code and Agentic Development Tools

This equation gives an approximation: it relates the quantities while allowing an approximation.

A second, independently run measurement effort took a different approach: instead of asking whether an agent could solve one fixed set of tasks, it asked how long a task an agent could complete autonomously with 50% reliability, using human professional completion time as the unit. METR’s March 2025 study, compiled from 170 tasks and more than 800 human timing baselines across software engineering, cybersecurity and general reasoning work, reported that this “50%-task-completion time horizon” for frontier agents had been doubling approximately every seven months for six years running, and that the finding was robust to an order-of-magnitude error in the underlying measurements, which would…

Meanings in this article

  • T50T_{50}: the length of task, measured in human-hours, that a frontier agent could complete autonomously with 50% reliability at time t.
  • tt: the time or time index used in this relationship.
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