Pulse Alpha Is a Free Stealth Model on OpenCode

Pulse Alpha Free is a new stealth model, free on OpenCode since November 2. Nobody has said who built it. It’s a reasoning model with a 1M-token context window, text and image input, tool use, and low, high and max reasoning effort. OpenCode model list (opens in a new tab)

To use it, run /models in OpenCode and pick Pulse Alpha Free, or set opencode/pulse-alpha-free in your config. It works in Cameroon, but it’s blocked in the EU and a few other countries. We couldn’t find it on Command Code.

How good is it? No benchmarks yet. Guesses point to Tencent’s Hy4 or a new Thinking Machines model; none are confirmed. One early hands-on test (opens in a new tab) at max reasoning found it weak on strict instructions and spatial details: broken SVGs, reversed controls in a 3D game, and theme buttons that did nothing. These are one tester’s results, not controlled benchmarks.

Budget impact: Free, with no end date announced. Stealth previews usually end within a week or two. OpenCode says data you send during the free period may be kept and used to train the model, so keep client code and secrets out of it.

Verdict: test it, don’t depend on it. Try small tasks you can check fast, and compare it with the other free models on OpenCode, counting fixes and retries. Keep a fallback ready for when the preview ends. Check the OpenCode model list (opens in a new tab) for current terms.