Anthropic announced Dreaming five days ago at Code w/ Claude. I rebuilt it over a weekend for a single-developer crypto trading bot.   The first dream pass surfaced a clean time-of-day profit pattern. The next day's full-history backtest crushed that signal — zero variables passed Bonferroni, the walk-forward filter failed to generalize, and 69% of the 47-day loss turned out to be concentrated in three specific days.   Dreaming surfaced a hypothesis. The follow-up backtest disproved it. That is the right loop, and most "what is Dreaming" posts skip the second half.   This is the build, the finding, and the disproof.   What Anthropic's Dreaming actually does   Dreaming is a memory-consolidation feature for long-running Claude agents. When an agent has been working in a codebase or domain for hours or days, its context window fills with raw transcripts, tool outputs, partial conclusions, and contradictions.…