Agents
Long-Horizon Tasks
Tasks that take an agent many steps and a long time to finish, measured in hours of equivalent human work rather than one prompt and reply.
In depth
Tasks that take an agent many steps and a long time to finish, measured in hours of equivalent human work rather than one prompt and reply. METR measures this with the 50% time horizon: the length of task, timed by skilled humans, that a model completes successfully half the time. METR's paper found that frontier time horizons have doubled roughly every seven months since 2019. It attributes the gains mainly to better reliability and to models recovering from their own mistakes.
Primary source: arxiv.org
Example
In practice, developers reach for Long-Horizon Tasks when they need the capability described above as part of an AI feature or workflow.
Go deeper at Developers Digest
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FAQ
Common questions
What is Long-Horizon Tasks?
Tasks that take an agent many steps and a long time to finish, measured in hours of equivalent human work rather than one prompt and reply.
Why does Long-Horizon Tasks matter for AI developers?
Long-Horizon Tasks sits in the Agents part of the AI stack. Understanding it helps you make better decisions when building, debugging, and shipping AI features.
Where can I learn more about Long-Horizon Tasks?
Developers Digest publishes tutorials and videos that cover Agents topics including Long-Horizon Tasks. Check the blog and YouTube channel for hands-on walkthroughs.
Related
Related terms
Agents
METR Time Horizon
A capability metric from METR that describes what an AI system can do in human terms: the length of task, measured by how long skilled humans take to do it, that a model completes with 50% success.
Agents
LMArena
A public leaderboard that ranks models by crowdsourced human preference: a user submits a prompt, two anonymous models answer, and the user votes for the better response before the model names are revealed.
Agents
LLM Tracing
Recording each step of an LLM application as a tree of timed spans, so you can see which prompts, model responses, tool calls, and handoffs happened in one request and how long each took.
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