AI thought leader Riley Brown posted a video on X on June 10 showcasing Claude Fable 5, Anthropic’s flagship model released the previous day, claiming that with just two prompts he successfully cloned Lovable’s official AI software development platform program. In the post, he asserted, “Mythos is AGI,” sparking polarized debate within the developer community.
Confirmed Results of Riley Brown’s Prompt Comparison Test
（Source: Screenshot of Riley Brown’s post）
Based on the video published by Riley Brown, the direction of the two prompt contents is as follows:
Prompt 1: Instructs Claude Fable 5 to copy Lovable’s overall interface visuals and core programming logic
Prompt 2: Directs the cloning system to immediately build a “Notion-style dark notes app”
The test input the exact same development instructions into the official Lovable and the cloned version. The video shows that the clone powered by Claude Fable 5 performs better than the official version in the following areas: richer text editing capabilities (titles, underlines, tables); smoother real-time web editing; one-click opening of an external browser for full preview; and overall UI fidelity surpassing the official Lovable App.
Confirmed Feature List for 5 Prompt Versions
RileyBrown updated the post hours after it was released, expanding the prompts to 5, after which the clone was confirmed to have the following complete functions:
· Build, edit, and preview a Web App and a Mobile App in real time at the same time
· Built-in cloud sandbox environment (Sandbox); when enabled, it starts automatically and auto-closes after 60 minutes of inactivity
· Integrate a database (Database) and user identity authentication (Authentication) system
· Integrate voice-to-text (Voice-to-Text) functionality
Riley Brown also demonstrated that after receiving instructions, the cloned platform directly generates pure Swift code and previews an Apple Notes–style interface inside the app, while also providing a test installation link; in another post, he further confirmed that with a single prompt he completed a similar action-development tool build as Replit.
Two Different Positions Among the Developer Community
After the video was published, two different positions emerged among the developer community on X:
Skeptics: Developers expressing doubt said that what Riley demonstrated was essentially duplicating a relatively simple notes application and frontend interface on the same underlying LLM, arguing that “the arrival of AGI” is marketing talk, and that there is still a technical gap from true cross-domain general artificial intelligence (AGI) with autonomous awareness.
Enthusiasts: Most Web3 and AI front-line developers expressed agreement, pointing out that Claude Fable 5’s multimodal performance in logical reasoning and long, complex tasks indicates a real paradigm shift in AI software engineering. Riley Brown himself also repeatedly confirmed the judgment “Mythos is AGI” in his posts.
FAQ
When was Claude Fable 5 released, and when was the video published?
Anthropic released Claude Fable 5 (internal codename Mythos) on June 9, 2026. Riley Brown’s cloned demonstration video was published on June 10, 2026 (Taipei time), less than 24 hours before Claude Fable 5 went live.
Compared with the official Lovable, which functions has Riley Brown’s clone been confirmed to do better in?
Based on the comparison test results confirmed in the video, Riley’s clone is better than the official Lovable App in text editing richness (titles, underlines, tables), real-time web editing smoothness, and one-click external browser preview functionality. The video also shows that the UI fidelity surpasses the official version.
What are the main arguments behind the developer community’s skepticism toward the “AGI declaration”?
According to the records of community discussion, the skeptics’ main arguments are: what Riley showed was the replication of a relatively simple notes application and frontend interface on the same underlying LLM, and that there remains a clear technical gap between this and true cross-domain general artificial intelligence (AGI) with autonomous awareness.
