gitでPermission denied (publickey)と言われた時の解決法

npm　installでローカルのモジュールをインストールしたいときにこんなエラーが出た

/usr/bin/git ls-remote -h -t ssh://[e-mail]/hoge.git

Permission denied (publickey).
fatal: Could not read from remote repository.
Please make sure you have the correct access rights
and the repository exists.

exited with error code: 128
exit [ 1, true ]

ssh-add ~/.ssh/id_rsa

でいけた。