A task that takes many dependent steps and a long time to finish, such as building a feature or carrying out an investigation. The research group METR measures an agent's progress by how long the tasks it can complete, at a set success rate, take a skilled person.
See also
- Agent harness
The software around a model that turns it into an agent: it runs the model step after step and hands it its tools and context.
- Context engineering
Deciding what goes into a model's context window at each step (instructions, files, tool results, memory) so an agent has what it needs and nothing that distracts it.
Cite this term.
CC BY 4.0, attribution required.
Orbyt Labs, Long-horizon task (AI Glossary), Oct 18, 2026. https://www.orbytlabs.ai/orbyt-collective/glossary/long-horizon-task
Orbyt Labs Glossaries (Oct 19, 2026), https://www.orbytlabs.ai/glossary#dataset
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