Amazon Bedrock AgentCore を使ってモダンな UI の AI エージェントを IaC 付きで構築しよう

aws login

rm -rf .eslintrc.cjs *.md LICENSE
rm -rf amplify/data public src/assets

npm install react-markdown

from strands import Agent
from strands_tools.rss import rss
from bedrock_agentcore.runtime import BedrockAgentCoreApp

app = BedrockAgentCoreApp()


def convert_event(event) -> dict | None:
    """Strandsのイベントをフロントエンド向けJSON形式に変換"""
    try:
        if not hasattr(event, 'get'):
            return None

        inner_event = event.get('event')
        if not inner_event:
            return None

        content_block_delta = inner_event.get('contentBlockDelta')
        if content_block_delta:
            delta = content_block_delta.get('delta', {})
            text = delta.get('text')
            if text:
                return {'type': 'text', 'data': text}

        content_block_start = inner_event.get('contentBlockStart')
        if content_block_start:
            start = content_block_start.get('start', {})
            tool_use = start.get('toolUse')
            if tool_use:
                tool_name = tool_use.get('name', 'unknown')
                return {'type': 'tool_use', 'tool_name': tool_name}

        return None
    except Exception:
        return None


@app.entrypoint
async def invoke_agent(payload, context):
    prompt = payload.get("prompt")

    agent = Agent(
        model="jp.anthropic.claude-haiku-4-5-20251001-v1:0",
        system_prompt="aws.amazon.com/about-aws/whats-new/recent/feed からRSSを取得して",
        tools=[rss]
    )

    async for event in agent.stream_async(prompt):
        converted = convert_event(event)
        if converted:
            yield converted


if __name__ == "__main__":
    app.run()

botocore
bedrock-agentcore
strands-agents
strands-agents[otel]
strands-agents-tools[rss]

FROM ghcr.io/astral-sh/uv:python3.13-bookworm-slim
WORKDIR /app

ENV UV_SYSTEM_PYTHON=1 \
    UV_COMPILE_BYTECODE=1 \
    UV_NO_PROGRESS=1 \
    PYTHONUNBUFFERED=1 \
    DOCKER_CONTAINER=1 \
    AWS_REGION=ap-northeast-1 \
    AWS_DEFAULT_REGION=ap-northeast-1

COPY requirements.txt requirements.txt
RUN uv pip install -r requirements.txt
RUN uv pip install aws-opentelemetry-distro==0.12.2

RUN useradd -m -u 1000 bedrock_agentcore
USER bedrock_agentcore

EXPOSE 8080
EXPOSE 8000

COPY . .

HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
  CMD curl -f http://localhost:8080/ping || exit 1

CMD ["opentelemetry-instrument", "python", "-m", "app"]

import { Stack } from 'aws-cdk-lib';
import * as agentcore from '@aws-cdk/aws-bedrock-agentcore-alpha';
import * as iam from 'aws-cdk-lib/aws-iam';
import { Platform } from 'aws-cdk-lib/aws-ecr-assets';
import { ContainerImageBuild } from 'deploy-time-build';
import { IUserPool, IUserPoolClient } from 'aws-cdk-lib/aws-cognito';
import * as path from 'path';
import { fileURLToPath } from 'url';

export function createAgentCoreRuntime(
  stack: Stack,
  userPool: IUserPool,
  userPoolClient: IUserPoolClient
) {
  const agentImage = new ContainerImageBuild(stack, 'AgentImage', {
    directory: path.dirname(fileURLToPath(import.meta.url)),
    platform: Platform.LINUX_ARM64,
  });

  const stackNameParts = stack.stackName.split('-');
  const rawEnvId = stackNameParts.length >= 4 ? stackNameParts[3] : stack.stackName.slice(-10);
  const envId = rawEnvId.replace(/[^a-zA-Z0-9]/g, '').toLowerCase();

  const runtime = new agentcore.Runtime(stack, 'UpdateCheckerRuntime', {
    runtimeName: `update_checker_${envId}`,
    agentRuntimeArtifact: agentcore.AgentRuntimeArtifact.fromEcrRepository(
      agentImage.repository,
      agentImage.imageTag
    ),
    authorizerConfiguration: agentcore.RuntimeAuthorizerConfiguration.usingCognito(
      userPool,
      [userPoolClient],
    ),
    networkConfiguration: agentcore.RuntimeNetworkConfiguration.usingPublicNetwork(),
  });

  runtime.addToRolePolicy(
    new iam.PolicyStatement({
      actions: [
        'bedrock:InvokeModel',
        'bedrock:InvokeModelWithResponseStream'
      ],
      resources: [
        'arn:aws:bedrock:*::foundation-model/*',
        'arn:aws:bedrock:*:*:inference-profile/*',
      ],
    })
  );

  return { runtime };
}

import { defineBackend } from '@aws-amplify/backend';
import { auth } from './auth/resource';
import { createAgentCoreRuntime } from './agent/resource';

const backend = defineBackend({
  auth,
});

const agentCoreStack = backend.createStack('AgentCoreStack');

const { runtime } = createAgentCoreRuntime(
  agentCoreStack,
  backend.auth.resources.userPool,
  backend.auth.resources.userPoolClient
);

backend.addOutput({
  custom: {
    agentRuntimeArn: runtime.agentRuntimeArn,
  },
});

ACCOUNT_ID=$(aws sts get-caller-identity --query Account --output text)
npx cdk bootstrap aws://$ACCOUNT_ID/ap-northeast-1

npm install
npx ampx sandbox