Vercel AI Updates: September 29, 2026

1. Claude Sonnet 5.5 Is Now Available on AI Gateway

Vercel. Vercel added Anthropic’s Claude Sonnet 5.5 to AI Gateway under the model ID anthropic/claude-sonnet-5.5, with Zero Data Retention supported. The model can be called through the AI SDK, the OpenAI-compatible Chat Completions and Responses APIs, or the Anthropic Messages API, and can be selected in coding agents connected to the gateway via npx vercel ai-gateway setup. Vercel describes it as an improvement on Claude Sonnet 5 for multi-step coding work that checks its own output, document and spreadsheet generation, desktop app use, and reading charts and technical drawings. Source