Claude Mythos 5.1

Claude Mythos 5.1 is the trusted-access sibling of Claude Fable 5.1. Ready to experience the power of AI? Start your journey here!

Platform: Replicate

Reasoning AIRestricted AccessCybersecurity AIScientific Research

Input: $10 per million tokens; Cache read: $0.25 per million tokens; Output: $50 per million tokens; trusted access required

Commercial

🚀Function Overview

A high-capability model available only through Anthropic trusted-access programs, with the Fable 5.1 specification profile and a different safeguard boundary.

Key Features

Stable model ID claude-mythos-5-1 for approved accounts
Same underlying model and specification profile as Claude Fable 5.1
1M-token context window and 128K-token maximum output
Adaptive thinking is always on
Text and image input with text output
Access is invitation-only and is not a general self-serve API option

Use Cases

•Approved defensive cybersecurity research
•Vetted life-science research under Anthropic's access program
•Controlled long-horizon scientific and technical investigation
•Governed evaluations where Fable safeguards would redirect the required task

⚙️Input Parameters

prompt

string

Text instructions for an approved trusted-access workflow

image

string

Optional image input for multimodal analysis

system_prompt

string

System-level instructions and governance constraints

effort

string

Reasoning effort control for adaptive thinking

max_tokens

integer

Maximum output length, up to 128K tokens

💡Usage Examples

Example 1

Input Parameters

{
  "prompt": "Review the approved defensive research question and propose an auditable evaluation plan within the program's access controls.",
  "system_prompt": "Stay within the authorized research scope and preserve evidence for independent review.",
  "effort": "high",
  "max_tokens": 8192
}

Output Results

I will define the authorized objective, excluded actions, evidence sources, and stop conditions before analysis.

The evaluation will separate observed results from inference and retain an auditable record of each decision.

Any step outside the approved access boundary will be returned for human review rather than executed.

Quick Actions

Use NowView Documentation

Technical Specifications

Hardware Type
Commercial Use: Supported
Pricing: Input: $10 per million tokens; Cache read: $0.25 per million tokens; Output: $50 per million tokens; trusted access required
Platform: Replicate

Related Keywords

Claude Mythos 5.1 accessclaude-mythos-5-1Project Glasswingtrusted access AIcybersecurity AI modellife science AI model

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