Context Rot
Also called long-context degradation, context degradation.
Context rot is the decline in a model's reliability as the amount of input in its context grows, even on simple tasks and well within its advertised context window.
Description
A 2025 study of 18 models found performance degrading with input length in ways that depended on the task and on the content around the relevant information, such as similar-looking distractors. It is a practical reason to keep contexts lean, retrieve only what is needed, and compact long histories rather than relying on maximum context length.
Sources
- Hong et al. (2025). Context Rot: How Increasing Input Tokens Impacts LLM Performance.
Cite this entry
Protologue. (2026). Context Rot. In Protologue: A Taxonomy of Prompting and LLM Techniques (v1.4.0, PTL-0169). https://protologue.com/t/context-rot/
BibTeX
@misc{protologue_context_rot,
title = {Context Rot},
author = {{Protologue}},
year = {2026},
howpublished = {Protologue: A Taxonomy of Prompting and LLM Techniques, v1.4.0},
note = {Entry PTL-0169},
url = {https://protologue.com/t/context-rot/}
}New terms, as they're coined
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