Summary
In mid-August 2026, Vercel added a harness layer to the AI SDK that lets developers run established coding-agent runtimes through a single unified interface, with support for any Agent Client Protocol (ACP)-compatible harness. Teams can switch between agent frameworks without changing application code.
What changed
The Vercel AI SDK introduced a harness layer that runs established coding-agent runtimes (such as Grok Build) through one unified interface and supports any Agent Client Protocol (ACP)-compatible harness, so applications can swap the underlying agent runtime without code changes.
Why it matters
Standardizing on ACP and a harness abstraction reduces lock-in to any single agent runtime and lets product teams treat coding agents as interchangeable backends. It strengthens Vercel's position as neutral infrastructure for shipping agent-powered apps.
Evidence excerpt
The AI SDK's harness layer lets developers run established coding-agent runtimes like Grok Build through one unified interface, now supporting any Agent Client Protocol (ACP)-compatible harness so teams can switch between agent frameworks without changing application code.