New pattern - Step Functions to Bedrock InvokeModel (CDK)

[NithinChandranR-AWS]

Description

This pattern deploys a Step Functions Express workflow that invokes Amazon Bedrock (Claude Sonnet) directly using the native InvokeModel optimized integration — no Lambda function required. Deployed with AWS CDK.

Key Features

• No Lambda — Step Functions calls Bedrock directly via BedrockInvokeModel L2 CDK construct
• Express workflow for synchronous sub-5-minute executions
• resultSelector extracts response text, model, and usage metadata
• Built-in retry with exponential backoff (3 attempts, 20s base interval)
• Inference profile ARN via ProvisionedModel.fromProvisionedModelArn (required for cross-region inference profiles)

Architecture

Step Functions (Express) ──▶ Amazon Bedrock (Claude Sonnet)

Testing

Deployed and tested on AWS account. Verified:

• SUCCEEDED execution status
• Successful Bedrock Claude Sonnet response with usage metadata
• Fixed: FoundationModel.fromFoundationModelId generates foundation-model ARN but inference profiles need inference-profile ARN — used ProvisionedModel.fromProvisionedModelArn with constructed ARN

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have made corresponding changes to the documentation (README.md)
• My changes generate no new warnings
• New and existing tests pass locally with my changes
• example-pattern.json included