New pattern - Step Functions to Bedrock InvokeModel (CDK)

sfn-bedrock-invokemodel-cdk/.gitignore

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+*.js
+*.d.ts
+node_modules
+cdk.out
+package-lock.json

sfn-bedrock-invokemodel-cdk/.npmignore

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+*.ts
+!*.d.ts
+cdk.out

sfn-bedrock-invokemodel-cdk/README.md

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+# Step Functions to Amazon Bedrock InvokeModel (CDK)
+
+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.
+
+Learn more about this pattern at Serverless Land Patterns: https://serverlessland.com/patterns/sfn-bedrock-invokemodel-cdk
+
+Important: this application uses various AWS services and there are costs associated with these services after the Free Tier usage - please see the [AWS Pricing page](https://aws.amazon.com/pricing/) for details. You are responsible for any AWS costs incurred. No warranty is implied in this example.
+
+## Requirements
+
+- [Create an AWS account](https://portal.aws.amazon.com/gp/aws/developer/registration/index.html) if you do not already have one and log in. The IAM user that you use must have sufficient permissions to make necessary AWS service calls and manage AWS resources.
+- [AWS CLI](https://docs.aws.amazon.com/cli/latest/userguide/install-cliv2.html) installed and configured
+- [AWS CDK](https://docs.aws.amazon.com/cdk/latest/guide/cli.html) installed
+- [Node.js](https://nodejs.org/) 18.x or later
+- [Amazon Bedrock model access](https://docs.aws.amazon.com/bedrock/latest/userguide/model-access.html) enabled for Anthropic Claude Sonnet in your AWS account
+
+## How it works
+
+Step Functions has a native optimized integration with Amazon Bedrock that lets you call `bedrock:InvokeModel` directly from a workflow state — no Lambda function needed. This reduces latency, cost, and operational complexity.
+
+**Key points:**
+- Uses `arn:aws:states:::bedrock:invokeModel` resource (optimized integration)
+- Express workflow for synchronous execution (lower cost, sub-5-minute executions)
+- Built-in retry with exponential backoff for transient failures
+- `resultSelector` extracts just the response text, model, and usage from the Bedrock response
+
+```
+┌──────────────────────┐         ┌──────────────────────┐
+│                      │         │                      │
+│   Step Functions     │────────▶│   Amazon Bedrock     │
+│   (Express)          │         │   Claude Sonnet      │
+│                      │◀────────│                      │
+└──────────────────────┘         └──────────────────────┘
+```
+
+## Deployment
+
+1. Install dependencies:
+   ```bash
+   cd sfn-bedrock-invokemodel-cdk
+   npm install
+   ```
+
+2. Deploy the stack:
+   ```bash
+   cdk deploy
+   ```
+
+## Testing
+
+Start a synchronous execution of the Express workflow:
+
+```bash
+aws stepfunctions start-sync-execution \
+  --state-machine-arn $(aws cloudformation describe-stacks \
+    --stack-name SfnBedrockInvokemodelStack \
+    --query 'Stacks[0].Outputs[?OutputKey==`StateMachineArn`].OutputValue' \
+    --output text) \
+  --input '{"prompt": "What are the benefits of Step Functions native Bedrock integration?"}' \
+  --query '{status: status, output: output}' \
+  --output json
+```
+
+The response includes the generated text, model ID, and token usage:
+
+```json
+{
+  "status": "SUCCEEDED",
+  "output": "{\"response\": \"...\", \"model\": \"claude-...\", \"usage\": {\"input_tokens\": 15, \"output_tokens\": 200}}"
+}
+```
+
+## Cleanup
+
+```bash
+cdk destroy
+```
+
+---
+
+Copyright 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+
+SPDX-License-Identifier: MIT-0

sfn-bedrock-invokemodel-cdk/bin/app.ts

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+#!/usr/bin/env node
+import "source-map-support/register";
+import * as cdk from "aws-cdk-lib";
+import { SfnBedrockInvokemodelStack } from "../lib/sfn-bedrock-invokemodel-stack";
+
+const app = new cdk.App();
+new SfnBedrockInvokemodelStack(app, "SfnBedrockInvokemodelStack");

sfn-bedrock-invokemodel-cdk/cdk.context.json

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+{
+  "acknowledged-issue-numbers": [
+    33623,
+    34635,
+    34892
+  ]
+}

sfn-bedrock-invokemodel-cdk/cdk.json

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+{
+  "app": "npx ts-node bin/app.ts"
+}

sfn-bedrock-invokemodel-cdk/example-pattern.json

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+{
+  "title": "Step Functions to Amazon Bedrock InvokeModel",
+  "description": "Invoke Amazon Bedrock directly from Step Functions using the native InvokeModel optimized integration — no Lambda function required. Deployed with AWS CDK.",
+  "language": "TypeScript",
+  "level": "200",
+  "framework": "CDK",
+  "introBox": {
+    "headline": "How it works",
+    "text": [
+      "This pattern deploys a Step Functions Express workflow that invokes Amazon Bedrock (Claude Sonnet) directly using the native bedrock:InvokeModel optimized integration.",
+      "No Lambda function is needed — Step Functions calls Bedrock directly, reducing latency, cost, and operational complexity.",
+      "The workflow accepts a prompt string as input, sends it to Bedrock, and returns the generated response with usage metadata.",
+      "Built-in retry logic handles transient failures with exponential backoff."
+    ]
+  },
+  "gitHub": {
+    "template": {
+      "repoURL": "https://github.com/aws-samples/serverless-patterns/tree/main/sfn-bedrock-invokemodel-cdk",
+      "templateURL": "serverless-patterns/sfn-bedrock-invokemodel-cdk",
+      "projectFolder": "sfn-bedrock-invokemodel-cdk",
+      "templateFile": "lib/sfn-bedrock-invokemodel-stack.ts"
+    }
+  },
+  "resources": {
+    "bullets": [
+      { "text": "Step Functions optimized integration for Amazon Bedrock", "link": "https://aws.amazon.com/about-aws/whats-new/2023/11/aws-step-functions-optimized-integration-bedrock/" },
+      { "text": "Build generative AI apps using Step Functions and Bedrock", "link": "https://aws.amazon.com/blogs/aws/build-generative-ai-apps-using-aws-step-functions-and-amazon-bedrock/" },
+      { "text": "Amazon Bedrock documentation", "link": "https://docs.aws.amazon.com/bedrock/latest/userguide/" }
+    ]
+  },
+  "deploy": {
+    "text": ["cdk deploy"]
+  },
+  "testing": {
+    "text": ["See the README for testing instructions."]
+  },
+  "cleanup": {
+    "text": ["cdk destroy"]
+  },
+  "authors": [
+    {
+      "name": "Nithin Chandran R",
+      "bio": "Technical Account Manager at AWS",
+      "linkedin": "nithin-chandran-r"
+    }
+  ],
+  "patternArch": {
+    "icon1": { "x": 20, "y": 50, "service": "sfn", "label": "Step Functions" },
+    "icon2": { "x": 80, "y": 50, "service": "bedrock", "label": "Amazon Bedrock" },
+    "line1": { "from": "icon1", "to": "icon2" }
+  }
+}

sfn-bedrock-invokemodel-cdk/lib/sfn-bedrock-invokemodel-stack.ts

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+import * as cdk from "aws-cdk-lib";
+import * as sfn from "aws-cdk-lib/aws-stepfunctions";
+import * as tasks from "aws-cdk-lib/aws-stepfunctions-tasks";
+import * as bedrock from "aws-cdk-lib/aws-bedrock";
+import * as logs from "aws-cdk-lib/aws-logs";
+import * as iam from "aws-cdk-lib/aws-iam";
+import { Construct } from "constructs";
+
+export class SfnBedrockInvokemodelStack extends cdk.Stack {
+  constructor(scope: Construct, id: string, props?: cdk.StackProps) {
+    super(scope, id, props);
+
+    const modelId = new cdk.CfnParameter(this, "BedrockModelId", {
+      type: "String",
+      default: "us.anthropic.claude-sonnet-4-20250514-v1:0",
+      description: "Bedrock inference profile model ID",
+    });
+
+    // Construct inference profile ARN for the model
+    const inferenceProfileArn = `arn:aws:bedrock:${this.region}:${this.account}:inference-profile/${modelId.valueAsString}`;
+    const model = bedrock.ProvisionedModel.fromProvisionedModelArn(
+      this,
+      "Model",
+      inferenceProfileArn
+    );
+
+    // Step Functions task: invoke Bedrock directly (no Lambda needed)
+    const invokeModel = new tasks.BedrockInvokeModel(this, "InvokeModel", {
+      model,
+      body: sfn.TaskInput.fromObject({
+        anthropic_version: "bedrock-2023-05-31",
+        max_tokens: 1024,
+        messages: [
+          {
+            role: "user",
+            content: sfn.JsonPath.stringAt("$.prompt"),
+          },
+        ],
+      }),
+      resultSelector: {
+        "response.$": "$.Body.content[0].text",
+        "model.$": "$.Body.model",
+        "usage.$": "$.Body.usage",
+      },
+    });
+
+    // Add retry for transient failures
+    invokeModel.addRetry({
+      errors: ["States.TaskFailed"],
+      interval: cdk.Duration.seconds(20),
+      maxAttempts: 3,
+      backoffRate: 2,
+    });
+
+    const logGroup = new logs.LogGroup(this, "LogGroup", {
+      logGroupName: "/aws/stepfunctions/sfn-bedrock-invokemodel",
+      retention: logs.RetentionDays.TWO_WEEKS,
+      removalPolicy: cdk.RemovalPolicy.DESTROY,
+    });
+
+    const stateMachine = new sfn.StateMachine(this, "StateMachine", {
+      stateMachineName: "sfn-bedrock-invokemodel",
+      definitionBody: sfn.DefinitionBody.fromChainable(invokeModel),
+      stateMachineType: sfn.StateMachineType.EXPRESS,
+      timeout: cdk.Duration.minutes(5),
+      logs: {
+        destination: logGroup,
+        level: sfn.LogLevel.ALL,
+        includeExecutionData: true,
+      },
+    });
+
+    // Grant Bedrock access (inference profile + foundation model)
+    stateMachine.addToRolePolicy(
+      new iam.PolicyStatement({
+        actions: ["bedrock:InvokeModel"],
+        resources: [
+          `arn:aws:bedrock:${this.region}:${this.account}:inference-profile/${modelId.valueAsString}`,
+          "arn:aws:bedrock:*::foundation-model/*",
+        ],
+      })
+    );
+
+    new cdk.CfnOutput(this, "StateMachineArn", { value: stateMachine.stateMachineArn });
+    new cdk.CfnOutput(this, "StateMachineName", { value: stateMachine.stateMachineName! });
+    new cdk.CfnOutput(this, "LogGroupName", { value: logGroup.logGroupName });
+  }
+}

sfn-bedrock-invokemodel-cdk/package.json

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+{
+  "name": "sfn-bedrock-invokemodel-cdk",
+  "version": "1.0.0",
+  "bin": { "app": "bin/app.ts" },
+  "scripts": { "build": "tsc", "cdk": "cdk" },
+  "dependencies": {
+    "aws-cdk-lib": "2.236.0",
+    "constructs": "10.4.2"
+  },
+  "devDependencies": {
+    "@types/node": "^22.0.0",
+    "ts-node": "^10.9.0",
+    "typescript": "~5.7.0"
+  }
+}

sfn-bedrock-invokemodel-cdk/tsconfig.json

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+{
+  "compilerOptions": {
+    "target": "ES2020",
+    "module": "commonjs",
+    "lib": ["es2020"],
+    "declaration": true,
+    "strict": true,
+    "noImplicitAny": true,
+    "strictNullChecks": true,
+    "noImplicitThis": true,
+    "alwaysStrict": true,
+    "noUnusedLocals": false,
+    "noUnusedParameters": false,
+    "noImplicitReturns": true,
+    "noFallthroughCasesInSwitch": false,
+    "inlineSourceMap": true,
+    "inlineSources": true,
+    "experimentalDecorators": true,
+    "strictPropertyInitialization": false
+  },
+  "exclude": ["cdk.out"]
+}