Developer Uses MCP Server to Fix AI-Generated Lambda Handler Missing SQS Trigger

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A developer found that Claude Code incorrectly generated an AWS Lambda handler by using event.body instead of the correct event.Records[0].body, because the AI could only read source files and not the actual AWS account configuration. The missing SQS event source mapping context caused the handler to throw an error on its first message. The developer resolved this by connecting an MCP server called Infrawise to Claude Code, which provided real infrastructure context including trigger types, event shapes, and account-level findings. With this setup, the AI correctly identified the SQS trigger shape, flagged the absence of a dead-letter queue on the orders-queue, and surfaced missing IAM permissions before deployment. The case highlights a broader limitation of AI coding assistants that rely solely on source code without access to live cloud infrastructure state.

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