Claude Fable 5.5 (Leaked Checkpoint) vs Gemini 3.8 Flash TTS
A direct, empirical evaluation of Claude Fable 5.5 (Leaked Checkpoint) (Anthropic) against Gemini 3.8 Flash TTS (Google DeepMind).
Claude Fable 5.5 (Leaked Checkpoint)
Developed by Anthropic · Proprietary Frontier Dynamic Reasoner parameters
Terminal-Bench 4.0 autonomous shell execution (78.5% target), recursive self-critique, and 1.5M-token repository refactoring.
Gemini 3.8 Flash TTS
Developed by Google DeepMind · Proprietary Multimodal Acoustic Flow Matching Transformer parameters
High-fidelity expressive podcasts, interactive video game dialogues, scripted multi-speaker conversations, and prompt-designed custom character voices.
| Metric | Claude Fable 5.5 (Leaked Checkpoint) | Gemini 3.8 Flash TTS |
|---|---|---|
| SWE-bench Verified | 84.2% | 64.2% |
| MMLU-Pro | 94.6% | 88.5% |
| MATH-500 | 98.4% | 91% |
| Context Window | 1,500,000 tokens | 128,000 characters input dialogue script |
| Input Pricing (per 1M) | $3.50 | $0.15 |
| Output Pricing (per 1M) | $17.50 | $15.00 |