Workflow Proof Kit is a model-agnostic system for turning one repeatable business task into a documented, reviewable human-in-the-loop AI workflow. It includes a setup guide, workflow map, decision gates, prompt cards for intake, context packing, drafting, critique, fact checking, and handoff, plus an evaluation rubric and change log. A fictional customer-support process demonstrates how to move from an ad-hoc request to a repeatable workflow with clear human review points. The kit uses invented examples, avoids proprietary brand frameworks, and is designed for practical adaptation by a solo operator or small team. It is a workflow documentation tool, not a guarantee of productivity, accuracy, revenue, or compliance. License: one buyer only; non-transferable; no resale, redistribution, sublicensing, marketplace upload, standalone client delivery, or competing derivative product. The source remains owned by the seller.