OpenAI's Heidel: compaction in Responses API lets GPT-6 Astra max out ARC-AGI-3
stevenheidel · x · 2026-09-04
OpenAI's Steven Heidel showed that turning on compaction in the Responses API allows GPT-6 Astra to max out ARC-AGI-3, highlighting context compaction as key to sustaining long-horizon agent tasks within limited context windows.
Related event: OpenAI Rolls Out Responses API Compaction, GPT-6 Astra Aces ARC-AGI-3(2 posts)→
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