The lumigo-cli is a collection of useful tools that makes serverless development easier, addressing various daily inconveniences such as not being able to see messages published to an SNS topic or switch between AWS profiles easily. The tool provides commands for listing Lambda functions, analyzing costs, tailing events from services like SNS and SQS, replaying SQS DLQ messages, removing CloudFormation stacks generated by the Serverless framework, and switching between AWS profiles. These features aim to improve the serverless development flow and provide fast feedback on system performance, making it easier for developers to work with event-driven architectures built on AWS services like Lambda, SNS, SQS, Kinesis Streams, and DynamoDB Streams.