AI agents win at Slay the Spire 2 after researchers replace growing chat logs with structured memory

Researchers developed AgenticSTS, which replaces AI agents' growing chat logs with five structured memory layers. Tested on the card game Slay the Spire 2, the agent won 6 out of 10 games, outperforming competing agents that won none. This approach keeps prompts at around 5,000 tokens instead of ballooning past 500,000.