Claude Mythos 5
Anthropic — Claude Mythos 5
Model Details
Claude Mythos 5 is Anthropic's most capable model for cybersecurity and life sciences, including vulnerability discovery, drug design, and biodefense screening. Access is currently limited due to the dual-use nature of these domains.
This model is a Preview and is made available to you as a "Beta Service" as defined in the AWS Service Terms. It is subject to your Agreement with AWS, the AWS Service Terms, and the applicable model EULA.
Model launch date: June 9, 2026
EOL no sooner than: June 9, 2027
Legacy period: at least 6 months
Model lifecycle policy: Model lifecycle (For Models Launched Prior to Sept 7 2026)
Model EOL date: N/A
End User License Agreements and Terms of Use: View
Model lifecycle: Active
Context window: 1M tokens
Max output tokens: 128K
Sampling parameters: temperature must be 1.0 or unset; top_p must be ≥ 0.99 and < 1.0, or unset; top_k is not supported
Reasoning: Supported (adaptive thinking is always on and cannot be disabled; effort level is configurable)
Knowledge cutoff: January 2026
Marketplace product ID: prod-kyryzgfmbtwtc
| Input Modalities | Output Modalities |
|---|---|
 Audio | Embedding |
 Image | Image |
| Speech | Speech |
| Text | Text |
| Video | Video |
Endpoints and APIs supported
The following tables show which endpoints and APIs are supported for Claude Mythos 5. For more information, see APIs supported by Amazon Bedrock and Endpoints supported by Amazon Bedrock.
Endpoint support
| Endpoint | Supported |
|---|---|
bedrock-runtime |
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bedrock-mantle |
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APIs supported on bedrock-runtime endpoint
| Messages | Responses | Chat Completions | Converse | Invoke |
|---|---|---|---|---|
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APIs supported on bedrock-mantle endpoint
| Messages | Responses | Chat Completions | Converse | Invoke |
|---|---|---|---|---|
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Capabilities and Features
Bedrock Features
Features supported using bedrock-mantle endpoint
Implicit and Explicit Prompt Caching using bedrock-mantle endpoint
For more information, see Prompt caching for faster model inference.
| Explicit Prompt Caching supported | Min tokens per cache checkpoint | Max cache checkpoints per request | Supported TTL | Fields that accept prompt cache checkpoint |
|---|---|---|---|---|
| Yes | 512 | 4 | 5 minutes, 1 hour | system, messages, and tools |
Pricing
This model is a third-party model offered and billed through AWS Marketplace. Charges appear on your AWS bill and in AWS Cost Explorer under the model provider (not under Amazon Bedrock). For pricing, see the Amazon Bedrock Pricing
Programmatic Access
Use the following model IDs and endpoint URLs to access this model programmatically. For more information about the available APIs and endpoints, see APIs supported and Endpoints supported.
| Endpoint | Model ID | In-Region endpoint URL | Geo inference ID | Global inference ID |
|---|---|---|---|---|
bedrock-mantle |
anthropic.claude-mythos-5 |
https://bedrock-mantle.{region}.api.aws/anthropic/v1/messages |
N/A | N/A |
For example, if region is us-east-1 (N. Virginia), then the bedrock-mantle endpoint URL will be "https://bedrock-mantle.us-east-1.api.aws/anthropic/v1/messages".
Service Tiers
Amazon Bedrock offers multiple service tiers to match your workload requirements. Standard provides pay-per-token access with no commitment (set "service_tier": "default" or omit the field). Priority delivers the fastest response times for a price premium (set "service_tier": "priority"). Flex provides lower-cost access for flexible, non-time-sensitive workloads (set "service_tier": "flex"). Reserved provides dedicated throughput with a term commitment for predictable workloads; it is set at the account level rather than per request (contact your AWS account team to enable). For more information, see service tiers.
| Standard | Priority | Flex | Reserved |
|---|---|---|---|
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Regional Availability
Regional availability at a glance
Amazon Bedrock offers three inference options: In-Region keeps requests within a single Region for strict compliance, Geo Cross-Region routes across Regions within a geography (such as US, EU, and APAC) while respecting data residency, and Global Cross-Region routes anywhere worldwide when there are no residency constraints. Refer to the Regional availability by models page for more details.
Availability differs by endpoint.
Availability using the bedrock-mantle endpoint
| Region | In-Region | Geo | Global |
|---|---|---|---|
us-east-1 (N. Virginia) | | | |
Data retention
To use this model, you must opt in to provider data sharing by setting your data retention mode to provider_data_share via the Data Retention API. For more information, see Amazon Bedrock abuse detection.
Quotas and Limits
Your AWS account has default quotas to maintain the performance of the service and to ensure appropriate usage of Amazon Bedrock. The default quotas assigned to an account might be updated depending on regional factors, payment history, fraudulent usage, and/or approval of a quota increase request. For more information, see Quotas for Amazon Bedrock documentation and see the limits for the model.
Sample Code
Step 1 - AWS Account: If you have an AWS account already, skip this step. If you are new to AWS, sign up for an AWS account
Step 2 - API key: Go to the Amazon Bedrock console
Step 3 - Get the SDK: To use this getting started guide, you must have Python already installed. Then install the relevant software depending on the APIs you are using.
pip install -U "anthropic[bedrock]"
Step 4 - Set environment variables: Configure your environment to use the API key for authentication.
AWS_BEARER_TOKEN_BEDROCK="<provide your Bedrock API key>"
Step 5 - Run your first inference request: Save the file as bedrock-first-request.py
from anthropic import AnthropicBedrockMantle client = AnthropicBedrockMantle(aws_region="us-east-1") message = client.messages.create( model="anthropic.claude-mythos-5", max_tokens=1024, messages=[{"role": "user", "content": "Hello, Claude"}], ) print(message.content[0].text)