Vercel's AI Gateway adds Glyph Cluster, a free stealth model
An anonymous reasoning model for coding and long-context work is free to call through AI Gateway during its early-access period, with a 256,000 token context window.
Vercel added Glyph Cluster to AI Gateway on 7 October: a reasoning model whose maker isn’t disclosed, released under the “stealth” label while in early access. Vercel describes it as built for coding and long-context analysis — reviewing code, explaining failures, debugging, proposing changes, and reasoning through implementation options, alongside general planning, synthesis and quantitative work. It supports function calling and streams responses, with a 256,000 token context window and the same limit on output.
It’s free for teams on Pro and Enterprise plans with AI Gateway credits, callable as stealth/glyph-cluster through the AI SDK, an OpenAI-compatible Chat Completions endpoint, or supported coding agents:
import { streamText } from 'ai';
const result = streamText({
model: 'stealth/glyph-cluster',
prompt: 'Plan a migration from Express to Next.js route handlers.',
});Why it matters: a free, no-signup way to benchmark an unreleased model against whatever you’re already running for coding or agentic work, through infrastructure you likely already have an API key for.
The caveat: zero data retention isn’t available for this model, and Vercel says prompts and responses sent through it may be used for training. Don’t route anything sensitive through it during the stealth period.