wtf is caller?

Caller is a lightweight command-line tool that tells you which AWS account and identity you're currently logged into. Instead of installing heavy tools like the AWS CLI (which requires Python or Node), you just download a single binary file for your computer and run it. It's that simple. When you run the tool, it checks your AWS credentials and asks AWS "who am I?" It then displays your ARN, a unique identifier that shows your AWS account ID and the role or user you're using. If something goes wrong, like you don't have valid credentials set up, it exits with an error so other scripts can detect the failure. The tool has no external dependencies, meaning you don't need to install Python, Node, Java, or anything else to make it work. This is useful for developers and DevOps engineers who work with multiple AWS accounts or roles. For example, if you're switching between different team environments (a dev account and a production account), you can quickly verify you're logged into the right one before running any dangerous commands. It's also handy in automated scripts where you need to confirm credentials are valid before proceeding. The portability matters too, the same binary works across Windows, Mac, and Linux without recompilation. The project trades advanced AWS features for simplicity. It's narrowly focused on answering one question: "What AWS identity am I using right now?" If you need to actually manage AWS resources, you'd still use the full AWS CLI. But for a quick identity check in scripts or before important operations, this tool gets the job done without the overhead.