Claude Haiku 5.5

Overview. Claude Haiku 5.5 is Anthropic's high-speed multimodal model designed for low-latency inference workloads. It processes text and visual inputs across a 1,000,000-token context window with support for up to 128,000 generated tokens. Developers select Haiku 5.5 when rapid response generation and large document ingestion take precedence over frontier-scale parameter counts.

Key strengths. The model pairs real-time latency with extensive ingestion capacity, accepting text, images, and document files up to 1,000,000 tokens. It supports adaptive extended thinking with five configurable reasoning effort levels ranging from low to maximum, allowing runtime calibration of deliberate problem solving. Evaluation profiles demonstrate particular strength in direct communication, writing synthesis, and high-volume document research.

When to use it. Deploy Claude Haiku 5.5 for customer-facing communication agents, real-time triage, and rapid document digestion over extended context inputs. It functions effectively within the Smart Router for medium-complexity tasks that demand low latency. Workloads requiring deep mathematical reasoning or complex agentic loops should route to higher-tier models.

Limitations. Claude Haiku 5.5 operates strictly as a closed-weight hosted API and cannot be self-hosted. The model rejects custom temperature settings at the API level, returning client errors if non-default sampling values are supplied, and does not support native audio processing.

Sovereignty note. Anthropic is based in the United States and subject to the US CLOUD Act. Inference processed via proprietary Anthropic endpoints does not meet European Sovereign deployment standards.