It stores the API keys at ~/.config on the host (and that is mounted inside the container). Dockerfile can be found 
here and one can use it to build image locally if intended to. 
Example usage: 
docker run --rm -v ~/.config:/root/.config -it anuragbhatia/ripe-atlas-tools ripe-atlas measure traceroute --from-country IN --target he.net 
One can set an alias in the local shell to make it appear almost like a locally installed setup. 
E.g on fish:
anurag@Anurags-MacBook-Pro ~> alias ripe-atlas='docker run --rm -v ~/.config:/root/.config -it anuragbhatia/ripe-atlas-tools ripe-atlas'
anurag@Anurags-MacBook-Pro ~> funcsave ripe-atlas
anurag@Anurags-MacBook-Pro ~>
Thus the reduces syntax is alias becomes: 
ripe-atlas measure traceroute --from-country IN --target he.net 
Please do share if anyone has any feedback. 
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