AI tool comparison
ClawBench vs OpenMythos
Which one should you ship with? Here is the side-by-side panel verdict, pricing read, reviewer split, and community vote comparison.
Research
ClawBench
153 real-world browser tasks, live websites — best AI agent scores only 33%
75%
Panel ship
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Community
Free
Entry
ClawBench is a browser agent evaluation framework built around 153 real-world tasks running on 144 live production websites — not simulated environments or curated sandboxes. Tasks span e-commerce, travel booking, SaaS dashboards, government portals, and developer tools. A built-in request interceptor blocks genuinely irreversible actions (payments, form submissions that send data) so evaluations can run safely on real sites. The benchmark records five layers of data per run: session replays, screenshots at each decision point, raw HTTP traffic, agent reasoning traces, and browser action sequences. This makes failure analysis tractable — you can see exactly which DOM element the agent misidentified, not just a final score. The dataset is open and the evaluation harness is reproducible. The headline finding is sobering: Claude Sonnet 4.6, the best performer, completes only 33.3% of tasks. GLM-5 is second at 24.2%. No model exceeds 50% on any individual task category. The implication is stark — current browser agents are far from autonomous on the open web, and the gap between benchmark performance and production performance is still enormous.
Research
OpenMythos
Open-source PyTorch reconstruction of Claude Mythos — 770M matches 1.3B performance
75%
Panel ship
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Community
Paid
Entry
OpenMythos is an independent open-source effort to reconstruct the architectural innovations behind Anthropic's Claude Mythos model family, implemented in PyTorch and released under a permissive license. The headline claim: their 770M-parameter model matches the benchmark performance of standard 1.3B transformer architectures — a 40%+ parameter efficiency gain derived from their interpretation of the Mythos architectural improvements. The project focuses specifically on the structural innovations that make Mythos unusually efficient: the sparse attention mechanisms, context compression techniques, and routing strategies that allow the model to handle long-context tasks without proportional compute scaling. The team has published ablation studies showing which components drive the efficiency gains. This lands in the middle of growing open-source reverse engineering of proprietary model architectures, a trend that has previously produced projects like LLaMA reconstructions and Mamba implementations. For researchers without Anthropic API budgets, OpenMythos could become a useful local proxy for Mythos-style tasks — especially given that Claude Mythos capabilities are now central to Anthropic's commercial offering.
Reviewer scorecard
“The five-layer recording (replays, HTTP traffic, reasoning traces) is the right approach for actual debugging — finally a benchmark where failure analysis is tractable. The 33% score also sets honest expectations for teams planning to ship production browser agents right now.”
“A 770M model that matches 1.3B performance is meaningfully useful for edge deployment and local inference. Even if the efficiency claims hold up at only 80%, this is worth benchmarking against your specific tasks before committing to cloud API spend.”
“Live website testing is a double-edged sword: sites change their DOM, anti-bot measures evolve, and a task that passes today may fail next week with no code change. Benchmark drift on live websites could make ClawBench scores meaningless over 6-month periods without constant maintenance.”
“The efficiency claim needs independent verification badly — 'matches 1.3B performance' on whose benchmarks, with what tasks? Architectural reconstructions of proprietary models often cherry-pick favorable comparisons. And there's a real question about IP exposure if you ship products built on a reversed-engineered Anthropic architecture.”
“33% on live websites is actually more impressive than it sounds given the adversarial diversity of the real web. The trajectory from 5% in 2024 to 33% in 2026 means we're likely crossing 60% in 18 months — at which point browser agents start displacing RPA software at scale.”
“Open reconstruction of frontier architectures is how ML progress diffuses through the research community. Every major architecture innovation — attention, RLHF, MoE — became broadly available because researchers reverse-engineered and published it. Mythos efficiency techniques becoming open will accelerate the whole field.”
“As someone who uses browser agents for research and competitor monitoring, the failure mode analysis is exactly what I need. Knowing which website categories agents handle well (dev tools) vs. poorly (government portals) helps me route tasks appropriately right now.”
“For studios and creative teams that want to run AI pipelines locally without cloud costs, a 770M model with 1.3B-level quality on writing and summarization tasks would be legitimately game-changing. The VRAM requirements alone make this worth testing.”
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