dicnunz/codex-build-gate-skill

Build Gate is a skill for the Codex AI coding tool that stops it from immediately writing code for a new startup idea before that idea has been checked against some basic evidence. The problem it addresses is that Codex can build a full product in one sitting, which means it can just as easily build the wrong product quickly. Build Gate forces the idea through a check for buyer proof, a look at how people currently solve the problem, a list of reachable first customers, and a two week plan for testing the idea, before Codex is allowed to start implementing. If an idea does not pass this check, Codex will not write product code. Instead it gives you a smaller, more achievable next step to gather more proof. The output is a structured packet with a result of Pass, Hold, Pivot, or Kill, a ledger that separates what has been provided, verified, assumed, or is still unknown, a map of how people currently handle the problem without your product, and a two week validation plan with clear pass, fail, and kill criteria. It also suggests ten concrete next moves for reaching real buyers, rather than generic advice to go talk to users. You install it by running a single npx command that pulls it from GitHub, then restart Codex so it picks up the new skill. To use it, you describe your idea, the target customer, and what you want them to do, prefixed with a command that invokes the skill. The installer is non destructive, meaning it will not overwrite an existing skill with the same name unless you explicitly force it, and it can create a backup first. It is aimed at solo founders and small teams using Codex who want a forced pause for evidence before committing build time to an unproven idea.