From the source
Amazon announced the availability of Anthropic's Claude Haiku 5.5 on Amazon Bedrock and the Claude Platform on AWS.
The model is described as the fastest and most efficient in the Claude 5.5 family, costing around 75 percent less than Claude Haiku 4.5 for most tasks, and is the first Haiku model with effort controls to tune cost against intelligence per task.
It is designed for subagents and high-volume, cost-sensitive work, including coding, tool use, computer use, and agentic tasks.