DM failure

[Quantum-cross]

Trying to DM someone with a code snippet and I get this output:

~ » xclip -o | slackcat -u someone
/home/robert/.gem/ruby/2.2.0/gems/slackcat-0.2.5/bin/slackcat:17:in `block in get_objects': error retrieving members from users.list: missing_scope (RuntimeError)
    from /home/robert/.gem/ruby/2.2.0/gems/httparty-0.13.7/lib/httparty/response.rb:35:in `tap'
    from /home/robert/.gem/ruby/2.2.0/gems/slackcat-0.2.5/bin/slackcat:16:in `get_objects'
    from /home/robert/.gem/ruby/2.2.0/gems/slackcat-0.2.5/bin/slackcat:34:in `users'
    from /home/robert/.gem/ruby/2.2.0/gems/slackcat-0.2.5/bin/slackcat:44:in `im_for_user'
    from /home/robert/.gem/ruby/2.2.0/gems/slackcat-0.2.5/bin/slackcat:126:in `block in <top (required)>'
    from /home/robert/.gem/ruby/2.2.0/gems/slackcat-0.2.5/bin/slackcat:125:in `map'
    from /home/robert/.gem/ruby/2.2.0/gems/slackcat-0.2.5/bin/slackcat:125:in `<top (required)>'
    from /home/robert/.gem/ruby/2.2.0/bin/slackcat:23:in `load'
    from /home/robert/.gem/ruby/2.2.0/bin/slackcat:23:in `<main>'

I have my API token setup correctly because this works:
echo "testing" | slackcat -c off-topic