Claude Mythos 5 wins on coding (100 vs 96). GPT-5.5 wins on price ($5 vs $10/1M input). For most workflows, Claude Mythos 5 is the stronger default — the frontier ceiling — same model as fable 5, safeguards lifted, partner-only.
The shortest way to see the safest default, the lower-cost option, and the specialist pick before you read deeper.
Claude Mythos 5 is the safest overall answer here when you want the strongest default instead of the lowest list price.
Meta: Llama 3.1 8B Instruct is the lower-cost option to start with when you still need useful output at scale.
GPT-5.5 is the better pick when response speed matters more than maximum reasoning depth.
Claude Mythos 5 leads on coding with a score of 100 vs 96 for GPT-5.5.
GPT-5.5 is cheaper at $5/1M input tokens vs $10/1M for Claude Mythos 5.
Claude Mythos 5 is the stronger default for coding tasks.
Choose Claude Mythos 5 for coding and research — frontier cybersecurity research.
Choose GPT-5.5 when agentic coding.
GPT-5.5 is the more cost-efficient option at $5/1M — worth considering if token volume is a concern.
Switch the scoring lens to see whether the top answer changes when you care more about cost, speed, or long-document work.
Anthropic / Premium / Jun 9, 2026
The frontier ceiling — same model as Fable 5, safeguards lifted, partner-only.
Ranks models by the broadest mix of coding, writing, research, and long-context usefulness.
You don't have vetted-partner access or don't need lifted safeguards — Fable 5 is the same model, generally available, at the same price.
The fastest way to see where the recommendation shifts when your priority changes.
The frontier ceiling — same model as Fable 5, safeguards lifted, partner-only.
Best OpenAI flagship for agentic coding, research, and computer-use work.
80.3% SWE-Bench Pro — tied with Fable 5 as the highest public coding score of any model
Safeguards lifted in some areas for advanced security and research workloads
Excels at complex, multi-step cybersecurity tasks under partner access
Same 1M-token context and 1932 GDPval-AA score as Fable 5
Not generally available — limited to vetted partners after Project Glasswing's private preview
Most teams should use Fable 5, which is the same model with standard safeguards
Premium $10/$50 pricing and a deliberate, high-latency profile
UseRightAI recommendations are based on practical decision factors people actually feel in day-to-day use.
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Claude Mythos 5 wins on more categories — coding, research, long context. GPT-5.5 is the better pick when agentic coding. The right choice depends on your specific use case.
GPT-5.5 is cheaper at $5/1M input and $30/1M output. Claude Mythos 5 costs $10/1M input and $50/1M output.
Both Claude Mythos 5 and GPT-5.5 have the same 1M context window.
Claude Mythos 5 is better for coding with a score of 100 vs GPT-5.5's 96 (out of 100). Claude Fable 5 is the overall coding leader in this directory at 100/100.
GPT-5.5 is faster with a balanced speed rating (score: 3) vs Claude Mythos 5's deliberate rating (score: 2).