Amazon Bedrock AgentCore runtime

Amazon Bedrock AgentCore is the managed container runtime that hosts the AVX supervisor agent. It handles container lifecycle, WebSocket connection management, SigV4 authentication, and session multiplexing, freeing the agent code to focus on orchestration.

Two runtime modes

AVX deploys two AgentCore runtimes from the same supervisor code base:

Runtime mode	Transport	Use case
Bidirectional voice (bidi)	WebSocket — persistent bidirectional stream	Amazon Connect voice, iOS/mobile companion app, hands-free driver experience
Text / HTTP	HTTP unary — request/response	Web chat, CMS Fleet Intelligence portal /assistant/chat route, API integrations

Both runtimes share the same supervisor agent logic and tool catalog; the difference is the Strands model class (BidiNovaSonicModel for voice, BedrockModel for text) and the entry-point file.

Runtime entry point pattern

The AgentCore runtime is wired through the Strands BedrockAgentCoreApp decorator:

from bedrock_agentcore.runtime import BedrockAgentCoreApp

app = BedrockAgentCoreApp()

@app.entrypoint                     
def handler(payload, context):      
    session_id = getattr(context, 'session_id', 'default')
    user_message = payload.get('prompt', '')
    # ... agent orchestration ...
    return str(result)

app.run()

For the bidi voice runtime the entry point uses @app.websocket instead, and the handler receives raw WebSocket frames rather than a payload dict. The BidiAgent.run(inputs, outputs) pump manages the bidirectional audio/transcript stream.

Execution role and IAM grants

The AgentCore execution role must trust bedrock-agentcore.amazonaws.com and carry grants for every AWS API the agent invokes at runtime. Key grants for AVX:

Grant	Purpose
bedrock:InvokeModel + bedrock:InvokeModelWithResponseStream on the supervisor inference profile and its underlying foundation-model ARNs	Strands ConverseStream calls for both the supervisor LLM and Nova 2 Sonic bidi
bedrock:InvokeModelWithBidirectionalStream on the Nova 2 Sonic foundation-model ARN (us-east-1)	Bidirectional audio streaming to Nova 2 Sonic
bedrock-agent-runtime:Retrieve on the ADP Knowledge Base ARN	Cross-account RAG grounding for reference tools
bedrock-agentcore:CreateEvent, BatchCreateMemoryRecords, RetrieveMemoryRecords	AgentCore Memory LTM reads and writes for session grounding
athena:StartQueryExecution, GetQueryExecution, GetQueryResults on the AVX Athena workgroup	Cross-region ADP data-lake queries at session-init time
lakeformation:GetDataAccess on *	Lake Formation credential vending for S3 access gated by column/row filters
dynamodb:GetItem, PutItem, Query on CMS tables	Live vehicle state and booking writes

Note

Foundation-model ARNs carry no account ID (arn:aws:bedrock:<region>::foundation-model/<id>). Cross-region inference-profile ARNs require the account ID (arn:aws:bedrock:<region>:<account>:inference-profile/<id>). Both forms must be present in the IAM policy for Strands ConverseStream to succeed.

Deployment

AVX uses the agentcore CLI from the AgentCore starter toolkit:

agentcore configure -e agents/supervisor/agentcore_app.py
agentcore deploy --auto-update-on-conflict \
  --env CMS_STAGE=staging \
  --env VSA_STAGE=staging \
  --env AWS_REGION=us-west-2 \
  --env NOVA_SONIC_REGION=us-east-1

The --auto-update-on-conflict flag updates an existing runtime in place (idempotent by runtime name). Environment variables injected via --env are available to the handler as os.environ values. The CDK stack (vsa-staging-core) provisions the execution role and supporting infrastructure; the AgentCore runtime itself is provisioned by the CLI outside CDK.