Vercel Sandbox can now run Terminal-Bench, SWE-bench and OSWorld with a single --env vercel flag
Shipped 17 September, Vercel Sandbox now supports Harbor, the open-source harness behind Terminal-Bench whose registry also includes SWE-bench, tau3-bench and OSWorld. Adding `--env vercel` to `harbor run` puts each trial in an isolated Firecracker microVM so runs parallelize past a single machine, requiring Harbor 0.22.0 or later. Network policy is enforced at the sandbox firewall outside the VM, and optional credential injection attaches secrets to outbound requests without them ever entering the sandbox. Paired with AI Gateway, one AI_GATEWAY_API_KEY reaches models across providers, with example identifiers like vercel_ai_gateway/anthropic/claude-fable-5. This makes running your own agent evals a config change rather than an infrastructure project.
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