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 # Jar-Updater
 
-A simple cli program used to replace a program's .jar file with another.
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+A simple cli program used to replace a program's .jar file with another.
+
+## Usage
+The software must be given one argument which is the download URL for the new file.
+The second argument (optional) is the program to be run after the new file has been downloaded (usually the program calling this software).
+The third argument is the new file name of the downloaded file. This is used when the file name in the URL might change.
+The fourth argument is the amount of seconds to wait before starting the download. This gives the calling software time to exit, making its executable readable.
+
+The software is limited to downloading .jar files from knarcraft.net, but can be extended by replacing the URL validator.
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