There is a nice JetBrains paper showing that summarization "works" as well as observation masking: https://arxiv.org/pdf/2508.21433 https://arxiv.org/pdf/2508.2

There is a nice JetBrains paper showing that summarization "works" as well as observation masking: https://arxiv.org/pdf/2508.21433 https://arxiv.org/pdf/2508.21433. In other words, summarization doesn't work well. On top of that, they summarize with the cheapest model (Haiku). Compression is different from summarization in that it doesn't alter preserved pieces of context + it is conditioned on the tool call intent