Claude Opus 4.7 vs OpenMythos

Claude Opus 4.7 is Anthropic's latest flagship model, released April 16. It scores 87.6% on SWE-bench Verified — a 13-point improvement over Claude Opus 4.6 — and 94.2% on GPQA, making it competitive with the top frontier models on coding and scientific reasoning benchmarks. The context window extends to 1 million tokens with substantially improved retrieval accuracy at the far end of the window. The release introduces "Routines" — a first-party feature for defining persistent agentic workflows that Claude can execute autonomously across multiple sessions. Routines are defined in structured YAML and can include tool calls, conditional logic, and human-in-the-loop checkpoints. Anthropic positions this as a more reliable alternative to custom agent frameworks for common use cases. Pricing remains unchanged from Opus 4.6: $5/M input tokens, $25/M output tokens. The vision input resolution has been increased by 3.3x, which meaningfully improves performance on documents, diagrams, and UI screenshots. Available via API immediately and rolling out to Claude.ai Pro and Team plans over the next week.

OpenMythos is a community-driven theoretical reconstruction of Claude Mythos's suspected architecture, implementing a Recurrent-Depth Transformer (RDT) — a looped transformer that recycles layers multiple times per forward pass for deeper reasoning without massive parameter growth. The project drew 10,100 GitHub stars in its first week, reflecting intense developer curiosity about what's powering Anthropic's latest generation models. The architecture has three stages: a Prelude (initial layers), a Recurrent Block (looped up to 32 times with shared weights), and a Coda (final layers). Rather than stacking hundreds of unique layers, the recurrent block runs the same weights multiple times with learned injection parameters updating hidden states between loops — enabling implicit chain-of-thought reasoning in continuous latent space without generating intermediate tokens. The project supports Grouped Query Attention (GQA) with optional Flash Attention 2, Multi-Latent Attention (MLA), and sparse MoE with routed and shared experts. Model scales range from 1B to 1T parameters. The key claim is that RDT achieves reasoning depth comparable to fixed-depth models with far more parameters, since computational complexity scales with loop iterations rather than layer count. This would explain how Claude Mythos achieves strong reasoning performance without the extreme parameter counts of brute-force scaling — though Anthropic has neither confirmed nor denied the architecture.