Claude Mythos 5
Anthropic's experimental Claude model for open-ended scientific inquiry and long-horizon reasoning, documented as limited to approved Project Glasswing researchers.
Newer version: Claude Mythos 5.1
Provider
Anthropic
Model family
Anthropic Claude
Multimodal LLM
Cost tier
Mythos
Status
Preview
Why teams choose it
Complex reasoning
Useful for workflows that require structured thinking, multi-step logic, and deeper analysis than lightweight models provide.
Long-context analysis
Helps teams summarize, compare, and extract insights from long documents without losing important nuance.
Coding and tools
Works well for code assistance, tool calling, and agent workflows where instructions must stay consistent across steps.
Cost-efficient routing
Useful as part of a routing stack where cheap models handle drafts and confirmations and this tier handles genuinely hard passages.
When not to use this
- Availability is limited; do not present it as a generally available production model.
Benchmarks
No independent or vendor benchmark scores in this catalog entry.
Technical specs
- Inputs
- text, image
- Outputs
- text
- License
- Proprietary limited access
- Capabilities
- scientific reasoning
- long-horizon reasoning
- multimodal
- experimentation
Anthropic Claude family lineup
Current models
Previous versions
Related models
Claude Mythos 5 FAQ
What is Claude Mythos 5?
Anthropic's experimental Claude model for open-ended scientific inquiry and long-horizon reasoning, documented as limited to approved Project Glasswing researchers.
When does Claude Mythos 5 fit best?
Scientific research pilots
What should teams watch out for with Claude Mythos 5?
Availability is limited; do not present it as a generally available production model.
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