LLM Design Breakthrough: Markdown 'Skill' Transforms Opus 4.5 UI Generation

The quest to combat ‘AI slop’ – generic, uninspired design output from large language models – has revealed a potent, unexpected solution in front-end UI generation. While initial assessments often favor models like Gemini 3 Pro for their out-of-the-box design capabilities, a recent comparative analysis highlights a critical advantage in steerability offered by Opus 4.5 when augmented with a specific ‘front-end design skill’ markdown file.

The research compared the design output of Gemini 3 Pro, Opus 4.5, GPT 5.2, and Kimmy K2.5 when tasked with creating a marketing homepage for an image generation studio, both with and without the aforementioned skill. By default, Opus 4.5 produced what were described as ‘awful’ designs, frequently featuring unappealing purple gradients and noise textures. In contrast, Gemini 3 Pro initially generated some of the ‘coolest’ and most varied designs, though it struggled significantly with tooling, instruction adherence, and prone to outright errors like crashing. GPT 5.2, even when instructed to avoid skills, often defaulted to using them, yielding repetitive, text-heavy, editorial-style layouts. The game-changer proved to be the ‘front-end design skill,’ a markdown file from Cloud Code’s GitHub. This file acts as a reusable context, explicitly guiding models away from ‘generic AI generated aesthetics’ such as overused fonts, cliche color schemes, and predictable layouts. When Opus 4.5 was exposed to this skill, its output underwent a ‘stunning’ transformation, producing ‘awesome’ and ‘usable’ designs with significantly improved UX considerations. Critically, Opus 4.5 demonstrated a superior ability to iterate on preferred designs, generating meaningful follow-ups that reflected user preferences, unlike Gemini 3 Pro, which struggled to produce relevant iterations, suggesting a reliance on baked-in templates rather than true contextual design. Community polls conducted during the demonstration reflected this shift, with a clear preference emerging for Opus 4.5 combined with the design skill due to its enhanced malleability and steerability.