AI Developer CLI architecture integrates a local LLM client with AWS Lambda-based tool execution through an AgentCore Gateway secured by IAM SigV4 authentication. The CLI client communicates via MCP endpoint to the gateway, which routes requests to Tool Lambda functions running Java 21 on ARM64 in a private VPC subnet, with cross-account Client Lambda for downstream API access. CloudWatch and X-Ray provide comprehensive observability across the pipeline, while KMS customer-managed keys encrypt sensitive data at rest and in transit. This pattern enables developers to leverage local LLM reasoning while securely executing AWS-hosted tools with fine-grained IAM controls and audit trails. Fork and customize this diagram on Diagrams.so to adapt VPC CIDR blocks, Lambda memory configurations, or add additional tool functions for your AI agent workload.