Perplexity
https://www.perplexity.ai
Built by a developer without significant AI involvement
The website is a highly sophisticated, custom-engineered web application built by human developers, and the text content consists of functional UI labels and feature descriptions rather than AI-generated prose.
Platform & Tech
The site uses a custom-built, high-performance stack (Vite, custom modules, and specialized CDNs) rather than AI-assisted website builders.
Code Patterns
The source code shows complex, hand-optimized JavaScript logic for session management, localization, and state handling, which is characteristic of professional human engineering.
Server Headers
The server configuration is standard for a high-traffic production environment and lacks any signatures of automated AI-generation tools.
AI Content
The text is functional UI copy (labels, prompts, and feature lists) designed for a specific product interface, not long-form content generated by an LLM.
AI Assessment
The site is a human-built product that happens to be an AI tool; it is not a site 'built by AI' in the context of website generation tools.