# Claude Mythos 5.1
##  Anthropic — Claude Mythos 5.1
## Model Details
Claude Mythos 5.1 is Anthropic's most capable model for cybersecurity defense and life sciences research, including threat intelligence, vulnerability discovery, red teaming, drug discovery, and biodefense screening.
Access is currently gated to a vetted set of organizations through Anthropic's trusted access programs, given 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:** September 1, 2026
+ **Model EOL date:** N/A
+ **End User License Agreements and Terms of Use:** [View](https://aws.amazon.com/legal/bedrock/third-party-models/)
+ **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 or unset; temperature and top\_p cannot be specified together; top\_k is not supported
+ **Reasoning:** Supported (adaptive thinking is always on and cannot be disabled; effort level configurable — low, medium, high, xhigh, max; default: high)
+ **Knowledge cutoff:** June 2026
+ **Marketplace product ID:** prod-k24dbcuykobku
| **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 5.1. For more information, see [APIs supported by Amazon Bedrock](apis.md) and [Endpoints supported by Amazon Bedrock](endpoints.md).
**Endpoint support**
| **Endpoint** | **Supported** |
| --- | --- |
| bedrock-runtime |  |
**APIs supported on `bedrock-runtime` endpoint**
| **Messages** | **Responses** | **Chat Completions** | **Converse** | **Invoke** |
| --- | --- | --- | --- | --- |
|  |  |  |  |  |
**Tip**
Whenever possible, we recommend using the `bedrock-runtime` endpoint for new applications. See [Endpoints supported by Amazon Bedrock](endpoints.md) for details.
## Capabilities and Features
***Bedrock Features***
**Features supported using `bedrock-runtime` endpoint**
| **Supported** | **Not Supported** |
| --- | --- |
| + [Response streaming](/bedrock/latest/APIReference/API_runtime_InvokeModelWithResponseStream.html)
+ [Prompt caching](prompt-caching.html)
+ [Abuse detection](abuse-detection.html)
+ [Guardrails](guardrails.html)
+ [Prompt optimization](prompt-management-optimize.html)
+ [Knowledge base](knowledge-base.html)
+ [Model evaluation](evaluation.html)
+ [Prompt management](prompt-management.html)
+ [Flows](flows.html)
+ [Agents](agents.html) | + [Intelligent prompt routing](prompt-routing.html) |
***Prompt caching using `bedrock-runtime` endpoint***
For more information, see [Prompt caching for faster model inference](prompt-caching.html).
| **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
For pricing information, see the [Amazon Bedrock Pricing](https://aws.amazon.com/bedrock/pricing/) page.
## 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](apis.html) and [Endpoints supported](endpoints.html).
| **Endpoint** | **Model ID** | **In-Region endpoint URL** | **Geo inference ID** | **Global inference ID** |
| --- | --- | --- | --- | --- |
| bedrock-runtime | anthropic.claude-mythos-5-1 | N/A | us.anthropic.claude-mythos-5-1 | global.anthropic.claude-mythos-5-1 |
*For example, if region is us-east-1 (N. Virginia), then the bedrock-runtime endpoint URL will be "https://bedrock-runtime.us-east-1.amazonaws.com".*
## 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](service-tiers-inference.html).
| **Standard** | **Priority** | **Flex** | **Reserved** |
| --- | --- | --- | --- |
|  |  |  |  |
## 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](models-region-compatibility.md) page for more details.
| **Region** | **In-Region** | **Geo** | **Global** |
| --- | --- | --- | --- |
| us-east-1 (N. Virginia) |  |  |  |
| us-east-2 (Ohio) |  |  |  |
| us-west-1 (N. California) |  |  |  |
| us-west-2 (Oregon) |  |  |  |
| ca-central-1 (Canada) |  |  |  |
| ca-west-1 (Calgary) |  |  |  |
| eu-central-1 (Frankfurt) |  |  |  |
| eu-central-2 (Zurich) |  |  |  |
| eu-north-1 (Stockholm) |  |  |  |
| eu-south-1 (Milan) |  |  |  |
| eu-south-2 (Spain) |  |  |  |
| eu-west-1 (Ireland) |  |  |  |
| eu-west-2 (London) |  |  |  |
| eu-west-3 (Paris) |  |  |  |
| ap-east-2 (Taipei) |  |  |  |
| ap-northeast-1 (Tokyo) |  |  |  |
| ap-northeast-2 (Seoul) |  |  |  |
| ap-northeast-3 (Osaka) |  |  |  |
| ap-south-1 (Mumbai) |  |  |  |
| ap-south-2 (Hyderabad) |  |  |  |
| ap-southeast-1 (Singapore) |  |  |  |
| ap-southeast-2 (Sydney) |  |  |  |
| ap-southeast-3 (Jakarta) |  |  |  |
| ap-southeast-4 (Melbourne) |  |  |  |
| ap-southeast-5 (Malaysia) |  |  |  |
| ap-southeast-6 (New Zealand) |  |  |  |
| ap-southeast-7 (Thailand) |  |  |  |
| il-central-1 (Tel Aviv) |  |  |  |
| me-central-1 (UAE) |  |  |  |
| me-south-1 (Bahrain) |  |  |  |
| af-south-1 (Cape Town) |  |  |  |
| sa-east-1 (São Paulo) |  |  |  |
| mx-central-1 (Mexico) |  |  |  |
## Data Retention
To use this model, you must opt in to provider data sharing by setting your data retention mode to `provider_data_share`. You can configure this in the Amazon Bedrock console or via the Data Retention API. For more information, see [Amazon Bedrock abuse detection](abuse-detection.html).
## 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](quotas-increase.html). For more information, see [Quotas for Amazon Bedrock](quotas.md) documentation and see the [limits](/general/latest/gr/bedrock.html#limits_bedrock) 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](https://portal.aws.amazon.com/billing/signup).
**Step 2 - API key:** Go to the [Amazon Bedrock console](https://console.aws.amazon.com/bedrock/home#/api-keys/long-term/create) and generate a long-term API key.
**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.
------
#### [ Messages API ]
```
pip install -U anthropic aws-bedrock-token-generator
```
------
#### [ Invoke/Converse API ]
```
pip install boto3
```
------
**Step 4 - Set environment variables:** Configure your environment to use the API key for authentication.
------
#### [ Messages API ]
```
AWS_BEARER_TOKEN_BEDROCK=""
```
------
#### [ Invoke/Converse API ]
```
AWS_BEARER_TOKEN_BEDROCK=""
```
------
**Step 5 - Run your first inference request:** Save the file as `bedrock-first-request.py`
------
#### [ Messages API ]
```
from anthropic import Anthropic
from aws_bedrock_token_generator import provide_token
token = provide_token(region="us-east-1")
client = Anthropic(
base_url="https://bedrock-runtime.us-east-1.amazonaws.com/anthropic",
api_key=token,
)
response = client.messages.create(
model="global.anthropic.claude-mythos-5-1",
max_tokens=1024,
messages=[{"role": "user", "content": "Can you explain the features of Amazon Bedrock?"}],
)
print(response)
```
------
#### [ Invoke API ]
```
import json
import boto3
client = boto3.client('bedrock-runtime', region_name='us-east-1')
response = client.invoke_model(
modelId='global.anthropic.claude-mythos-5-1',
body=json.dumps({
'anthropic_version': 'bedrock-2023-05-31',
'messages': [{ 'role': 'user', 'content': 'Can you explain the features of Amazon Bedrock?'}],
'max_tokens': 1024
})
)
print(json.loads(response['body'].read()))
```
------
#### [ Converse API ]
```
import boto3
client = boto3.client('bedrock-runtime', region_name='us-east-1')
response = client.converse(
modelId='global.anthropic.claude-mythos-5-1',
messages=[
{
'role': 'user',
'content': [{'text': 'Can you explain the features of Amazon Bedrock?'}]
}
]
)
print(response)
```
------