[Enhancement]: <Bedrock Converse Claude 3.7 Reasoning Support in Rust>

[zach-montes]

Background story

Hello, I am trying to use the Bedrock Converse API in Rust. I have successfully implemented multiple models, but am now trying and failing to include Reasoning in the latest Claude 3.7. I see support for it in other languages, but I cannot find any documentation or examples for enabling thinking mode and setting budget tokens in Rust. I am not sure if support has been added and I am writing the syntax incorrectly, if there is a bug, or if Rust just hasn't been caught up to include a reasoning config yet.

What does this example accomplish?

I want to enable thinking and budget_tokens limits to include reasoning in my Claude 3.7 model.

Which AWS service(s)?

AWS Bedrock Converse

Which AWS SDKs or tools?

• [ ] All languages
• [ ] .NET
• [ ] C++
• [ ] Go (v2)
• [ ] Java
• [ ] Java (v2)
• [ ] JavaScript
• [ ] JavaScript (v3)
• [ ] Kotlin
• [ ] PHP
• [ ] Python
• [ ] Ruby
• [x] Rust
• [ ] Swift
• [ ] Not applicable

Are there existing code examples to leverage?

Working off of the AWS Bedrock Converse Rust SDK examples here

Do you have any reference code?

// I have tried adding `additional_model_request_fields` as a `JSON` and as a `Document` object, but keep running into errors that it has to be the other type.

let json_value = serde_json::json!({
          "reasoning_config": {
              "type": "enabled",
              "budget_tokens": 3000
          }
        });

// Convert the JSON value to a string.
let json_string = serde_json::to_string(&json_value)
  .map_err(|e| format!("Failed to serialize JSON: {}", e))?;

// Convert the string to a Document.
let additional_model_request_fields = Document::from(json_string.as_str());

let response = client
    .converse()
    .model_id(model)
    .additional_model_request_fields(additional_model_request_fields)
    .messages(
        Message::builder()
            .role(ConversationRole::User)
            .content(ContentBlock::Text(prompt_template))
            .build()
            .map_err(|_| "failed to build message")?,
    )
    .send()
    .await;