The provided guide details the rigorous W3C Technical Architecture Group (TAG) review process that Chromium engineers must follow when proposing new web platform features. The TAG serves as an architectural steward for the web, primarily focused on providing high-level feedback to ensure proposed APIs adhere to established security, privacy, and design principles. Chromium initiates reviews at least twice—during the early design/incubation stage and again before a final "Intent to Ship"—requiring proponents to draft a comprehensive explainer and complete a Security and Privacy Self-Review. TAG feedback frequently addresses concerns regarding API consistency and architectural alignment, often resulting in necessary implementation adjustments to features like WebUSB and the controversial Idle Detection API. Although the TAG is advisory, successfully completing its review is crucial for building consensus across browser vendors and establishing a feature’s path toward becoming a widely accepted, interoperable web standard. This collaboration aims to increase the overall quality and success rate of web platform innovations.