# Configure response generation for reasoning models with Knowledge Bases
Certain foundation models can perform model reasoning, where they take a larger, complex task and break it down into smaller, simpler steps. This process, often referred to as chain of thought (CoT) reasoning, can improve model accuracy by giving the model a chance to think before it responds. Model reasoning is most useful for task such as multi-step analysis, math problems, and complex reasoning tasks. For more information, see [Enhance model responses with model reasoning](inference-reasoning.md).
**Note**
This page describes how to use the reasoning configuration specifically for Amazon Bedrock Knowledge Bases. For information about configuring reasoning for direct model invocation using the `InvokeModel` API, see [Enhance model responses with model reasoning](inference-reasoning.md).
When model reasoning is enabled, it can result in improved accuracy with better citation results but can result in a latency increase. The following are some considerations when you query the data sources and generate responses using reasoning models with Amazon Bedrock Knowledge Bases.
**Topics**
+ [Reasoning models](#kb-test-reasoning-models)
+ [Using model reasoning for Claude 3.7 Sonnet](#kb-test-reasoning-using)
+ [General considerations](#kb-test-reasoning-general-considerations)
+ [Retrieve and generate API considerations](#kb-test-reasoning-api-considerations)
## Reasoning models
To see which models support reasoning, please visit [models at a glance](model-cards.md) and choose the model you are interested in.
## Using model reasoning for Claude 3.7 Sonnet
**Note**
Model reasoning is always enabled for the DeepSeek-R1 model. The model does not support toggling the reasoning capability on and off.
When using the Claude 3.7 Sonnet model, model reasoning can be enabled or disabled using the `additionalModelRequestFields` parameter of the [https://docs.aws.amazon.com/bedrock/latest/APIReference/API_agent-runtime_RetrieveAndGenerate.html](https://docs.aws.amazon.com/bedrock/latest/APIReference/API_agent-runtime_RetrieveAndGenerate.html) API. This parameter accepts any key-value pairs. For example, you can add a `reasoningConfig` field and use a `type` key to enable or disable reasoning, as shown below.
```
{
"input": {
"text": "string",
"retrieveAndGenerateConfiguration": {
"knowledgeBaseConfiguration": {
"generationConfiguration": {
"additionalModelRequestFields": {
"reasoningConfig" : {
"type": "enabled",
"budget_tokens": INT_VAL, #required when enabled
}
}
},
"knowledgeBaseId": "string",
},
"type": "string"
},
"sessionId": "string"
}
```
## General considerations
The following are some general considerations for using the reasoning models for Knowledge Bases.
+ The reasoning models will have up to five minutes to respond to a query. If the model takes more than five minutes to respond to the query, it results in a time out.
+ To avoid exceeding the five-minute timeout, model reasoning is enabled only at the generation step when you configure your queries and response generation. The orchestration step cannot have model reasoning.
+ The reasoning models can use up to 8192 tokens to respond to queries, which will include both the output and thinking tokens. Any request that has a request for maximum number of output tokens greater than this limit will result in an error.
## Retrieve and generate API considerations
The following are some considerations when using the [https://docs.aws.amazon.com/bedrock/latest/APIReference/API_agent-runtime_RetrieveAndGenerate.html](https://docs.aws.amazon.com/bedrock/latest/APIReference/API_agent-runtime_RetrieveAndGenerate.html) API for the reasoning models.
+ By default, when reasoning is disabled for all models including the Claude 3.7 Sonnet, the temperature is set to zero. When reasoning is enabled, the temperature must be set to one.
```
"inferenceConfig": {
"textInferenceConfig": {
"maxTokens": 8192,
"temperature": 1
}
}
```
+ The parameter, Top P, must be disabled when reasoning is enabled for the Claude 3.7 Sonnet model. Top P is an additional model request field that determines the percentile of possible tokens to select from during generation. By default, the Top P value for other Anthropic Claude models is one. For the Claude 3.7 Sonnet model, this value will be disabled by default.
+ When model reasoning is in use, it can result in an increase in latency. When using this API operation and the [https://docs.aws.amazon.com/bedrock/latest/APIReference/API_agent-runtime_RetrieveAndGenerateStream.html](https://docs.aws.amazon.com/bedrock/latest/APIReference/API_agent-runtime_RetrieveAndGenerateStream.html) API operation, you might notice a delay in receiving the response from the API.