The ".artifacts" Folder - MeGysssTaa/keiko-plugin-inspector GitHub Wiki
About
In Keiko's working directory, you may have noticed a folder named .artifacts. You can guess by name that this folder stores files created as a result of some of Keiko's workflows, and that's correct. These files are not required by Keiko to work — you can safely delete the whole folder anytime. Usually, the contents of this folder are caches created by Keiko's analyses. They help Keiko remember the results of various calculations. This means that if this folder exists, then the next time you will start your server (with Keiko), Keiko will read most of the data from these files. This results in a much faster startup.
Be cautious when deleting particular files from this folder, though. Some files may be tied closely to each other, and Keiko may not be able to handle a situation where one of such "connected" files is present, but the other is missing. For safety, it is recommended to clean this folder using tool:clean, which will not only securely delete all files within the directory, but also print you some fancy statistics such as the number of files deleted and the number of bytes freed on your disk.
File format
Files within the .artifacts directory are usually stored as GZIP-compressed JSON UTF-8 text files. They are not encrypted. Do note that this format should be considered proprietary. You should not rely on these files or their format in any way. The format of all or particular files may be changed any time, with or without a special notice.