Claude 3.5 Haiku was the model that first proved a Haiku-tier release could match Opus-class performance, scoring strong results on SWE-bench Verified and redefining expectations for what fast, affordable models could accomplish on real engineering tasks.
import { streamText } from 'ai'
const result = streamText({ model: 'anthropic/claude-3.5-haiku', prompt: 'Why is the sky blue?'})Before Claude 3.5 Haiku arrived on November 6, 2023, the Haiku tier was the budget option: fast and cheap, but clearly a step down in capability. Claude 3.5 Haiku broke that assumption. Anthropic announced it matched Claude 3 Opus on many intelligence evaluations while running at speeds comparable to the original Claude 3 Haiku. The result: Opus-class reasoning at Haiku-class latency.
The SWE-bench Verified result crystallized this. At 40.6%, Claude 3.5 Haiku outperformed agents built on the original Claude 3.5 Sonnet and other comparable models at the time on real-world software engineering tasks: fixing bugs, implementing features, and navigating codebases. For a model designed for speed and low cost, posting that score on a benchmark requiring sustained multi-file reasoning was a landmark.
Anthropic designed the model for three deployment patterns: latency-sensitive user-facing products, specialized sub-agent roles inside agentic pipelines, and personalization engines processing large volumes of per-user data (purchase histories, pricing records, inventory feeds). Improved instruction following and more accurate tool use make it practical for the structured, schema-bound work that sub-agents handle in production systems.
The December 2024 pricing revision adjusted rates to $0.8 per million input tokens and $4.0 per million output tokens. If you modeled costs around launch pricing, verify against current rates.