When the RLI paper was published in October 2025, the best system, Manus, completed 2.5% of projects [3][2]. Fable 5 led at about 16% in July, and its direct predecessor Fable 5.1 scored 17.92% [1][2]. The current leaderboard:
| Model | Developer | Automation rate |
|---|---|---|
| Fable 5.2 | Anthropic | 41.30% |
| Opus 5.5 | Anthropic | 21.25% |
| GPT 6 Astra | OpenAI | 20.83% |
| Fable 5.1 | Anthropic | 17.92% |
| Gemini Argon 4 | 17.08% | |
| Fable 5 | Anthropic | 15.83% |
Source: Scale Labs RLI leaderboard [1].
The Decoder reported that Scale Labs saw the largest gains in audio and music editing, architecture and interior design, and 3D modeling, and that nearly 50 of Fable 5.2’s successful jobs were ones no agent had completed before [2]. Industrial product design and animation are still areas the AI “can barely handle,” according to Scale Labs; typical failures were amateur-quality work, incomplete or broken files, and contradictory designs [2].