Transformers.js 4.3 brings JSON-constrained decoding to the browser

Hugging Face released Transformers.js v4.3, whose headline feature is structured output: a new subpackage enables JSON Schema-constrained decoding to force models to emit valid JSON directly in the browser, alongside new models and WebGPU improvements.

2026-09-16 ~ 2026-09-16 · 3 related posts

• Transformers.js v4.3 ships browser-side structured output with JSON Schema constraints — Hugging Face · 2026-09-16
• Transformers.js v4.3.0 ships structured output: force exact JSON Schema in the browser — nicodotdev · 2026-09-16
• Transformers.js 4.3 ships structured output, new model architectures, and Safari WebGPU support — nicodotdev · 2026-09-16