diff --git a/tools/send-zone-with-errors.cr b/tools/send-zone-with-errors.cr
new file mode 100644
index 0000000..d30656c
--- /dev/null
+++ b/tools/send-zone-with-errors.cr
@@ -0,0 +1,86 @@
+require "authd"
+require "yaml"
+
+require "baguette-crystal-base"
+require "ipc"
+
+require "../src/network.cr"
+require "../src/storage.cr"
+require "../src/config"
+require "../src/client/lib/*"
+
+#
+# Create a zone with errors then try to add it to dnsmanager.
+# This also shows how to use IPC connections and the dnsmanager client library.
+# Real dnsmanager client is in `src/client/`.
+#
+
+alias DSZ = DNSManager::Storage::Zone
+
+if ARGV.size < 2
+	puts "usage: username pass"
+	exit 0
+end
+
+# Authentication
+login = ARGV[0]
+pass  = ARGV[1]
+
+begin
+	puts "authd: connection"
+	authd = AuthD::Client.new
+rescue e
+	puts "cannot contact authd:"
+	puts e.to_s
+	exit 1
+end
+
+puts "authd: sending login"
+token = authd.get_token? login, pass
+puts "authd: after receiving token, disconnection"
+authd.close
+
+unless token
+	puts "cannot obtain a token from authd"
+	exit 1
+end
+
+begin
+	puts "dnsmanager: connection"
+	dnsmanagerd = DNSManager::Client.new
+rescue e
+	puts "cannot contact dnsmanagerd:"
+	puts e.to_s
+	exit 1
+end
+
+puts "dnsmanager: sending login"
+dnsmanagerd.login token.not_nil!
+puts "dnsmanager: receiving login response"
+
+zone = DSZ.new "test.my-domain.com!!!"
+
+#
+# Invalid records
+#
+
+zone.resources << DSZ::A.new    "13931891",  600.to_u32, "127.0.0.1"
+zone.resources << DSZ::AAAA.new "www",  600.to_u32, "::10000"
+zone.resources << DSZ::MX.new   "mail", 600.to_u32, "!!", 5.to_u32
+zone.resources << DSZ::MX.new   "mail", 1.to_u32, "::1", 5.to_u32
+
+# PTR: 0.168.192.in-addr.net 60 example.com. 
+zone.resources << DSZ::PTR.new   "1.10.20.80.in-addr.arpa", 60.to_u32, "::1"
+zone.resources << DSZ::PTR.new   "1.10.20.80.mdr", 60.to_u32, "blah.com"
+
+zone.resources << DSZ::SOA.new   "mail", 60.to_u32, "::1",
+	"ma.zone.tld", "john\.doe.example.com"
+
+zone.resources << DSZ::NS.new   "mail", 60.to_u32, "::1"
+
+pp! dnsmanagerd.user_zone_add zone
+
+puts "dnsmanager: close"
+dnsmanagerd.close
+exit 0
+