The best alternatives to Directory Serve are GitHub, shell.how, and Noteli. If these 3 options don't work for you, we've listed a few more alternatives below.
What do you think of Directory Serve?
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shell.how explains how your shell command works. It uses open source data from Fig (https://fig.io) and supports descriptions for hundreds of CLI tools like git, npm/yarn, docker, and aws. Contribute today: https://github.com/withfig/autocomplete
Noteli is an Open Source CLI tool made especially for note-taking. Noteli is built using powers of TypeScript and security of Auth0 with MongoDB. Noteli would help developers to take notes quickly from the shell without wasting time through GUI :P