# Vercel adds Claude Opus 5.5 to AI Gateway with new request requirements

_Published Wednesday, September 23, 2026 at 4:05 PM EDT · AI, Infrastructure · Latest · Tier 2 — Notable_

![Vercel adds Claude Opus 5.5 to AI Gateway with new request requirements — Primary](https://assets.vercel.com/image/upload/contentful/image/e5382hct74si/1nxbUaUVfuEnDEKT9lRXrY/a709d6455cfbd73f7ef021e13322f8b4/Vercel_x_Anthropic.png)

Vercel has made Anthropic's Claude Opus 5.5 available through AI Gateway for applications and coding agents. It has a 1M-token context window and can return up to 128K tokens. Vercel says customers can call it through the AI SDK, OpenAI-compatible Chat Completions API and Anthropic Messages API.

The model changes how existing integrations must request reasoning and tools. Requests that disable thinking or set a fixed thinking budget receive HTTP 400 errors, and callers can no longer require a particular tool call. Developers using those controls must change their requests or handle missed tool calls in their own software.

## Sources

- [Vercel News](https://vercel.com/changelog/claude-opus-5-5-now-available-on-ai-gateway)

---
Canonical: https://techandbusiness.org/newswire/LPyjmlSNsQE-khb-zheptk
Published: 2026-09-23T20:05:50.056Z
Story chronology: 2026-09-22T00:00:00.000Z
Retrieved: 2026-09-23T21:38:32.902Z
Publisher: Tech & Business (techandbusiness.org)