impeccable-posttooluse-hook-zero-cost-design-gate

Impeccable’s 3,590-line JS engine (25 deterministic rules) can be wired as a PostToolUse hook on Write/Edit to .html/.css/.tsx/.jsx/.svelte/.astro files, running npx impeccable detect --json <file> inline. This creates a zero-LLM-cost quality gate that catches AI slop and design violations at every file write without burning tokens. All current design quality assessment in our frontend skills is LLM-based — this is the first deterministic layer.