Anthropic’s October 7, 2026 launch of Claude Haiku 5.5 completed the Claude 5.5 family just weeks after Sonnet 5.5 and Opus 5.5, delivering a 1M-token context window, adaptive effort settings, and roughly 75% lower average cost than Haiku 4.5 while posting large gains on computer-use and agentic benchmarks such as OSWorld 2.1. The move positions the lightweight model for high-volume tasks like summarization, classification, and subagent work alongside larger siblings, narrowing the gap to competitors including GPT-6 Luna on shared evaluations. With prior Haiku updates spaced roughly a year apart and the 5.x cadence accelerating in September–October, trader attention now centers on whether Anthropic will iterate to a 5.6+ version before year-end or sustain the current pricing and capability tier through 2027.