diff --git a/src/App/Messages.purs b/src/App/Messages.purs
index e83d6dc..4ae8ff1 100644
--- a/src/App/Messages.purs
+++ b/src/App/Messages.purs
@@ -1,49 +1,68 @@
 module App.Messages where
 
+import Prelude
+
 import Effect (Effect)
+import Effect.Console (log)
 
 import Data.Argonaut.Core as J
 import Data.Codec.Argonaut as CA
+import Data.Maybe
 import Data.Either
 import Data.Codec.Argonaut.Record as CAR
 
 -- Base types.
+type AuthDError = { reason :: Maybe String }
+type AuthDToken = { uid :: Int, token :: String }
+type AuthDContacts = { user :: Int, email :: Maybe String, phone :: Maybe String }
+
 type Email = String
 type Password = String
 type Login = { email :: Email, password :: Password }
-type Token = { token :: String }
 
 -- Their related JSON codecs.
-login_codec ∷ CA.JsonCodec Login
-login_codec = CA.object "Login" (CAR.record { email: CA.string, password: CA.string })
-token_codec ∷ CA.JsonCodec Token
-token_codec = CA.object "Token" (CAR.record { token: CA.string })
+authd_codec_error ∷ CA.JsonCodec AuthDError
+authd_codec_error = CA.object "AuthDError" (CAR.record { reason: CAR.optional CA.string })
+authd_codec_token ∷ CA.JsonCodec AuthDToken
+authd_codec_token = CA.object "AuthDToken" (CAR.record { uid: CA.int, token: CA.string })
+authd_codec_contacts ∷ CA.JsonCodec AuthDContacts
+authd_codec_contacts = CA.object "AuthDContacts" (CAR.record { user: CA.int, email: CAR.optional CA.string, phone: CAR.optional CA.string  })
+codec_login ∷ CA.JsonCodec Login
+codec_login = CA.object "Login" (CAR.record { email: CA.string, password: CA.string })
 
 -- All possible requests.
 data RequestMessage
   = MessageLogin Login
 
--- All possible answers.
-data AnswerMessage
-  = Logged Token
+-- All possible answers from the authentication daemon (authd).
+data AuthDAnswerMessage
+  = AuthenticationDaemonError AuthDError
+  | Logged AuthDToken
+  | Contact AuthDContacts
 
 encodeRequest ∷ RequestMessage → J.Json
 encodeRequest m = case m of
-    (MessageLogin login) -> CA.encode login_codec login
+    (MessageLogin login) -> CA.encode codec_login login
 
 -- TODO
 --rawSerialize :: RequestMessage -> ArrayBuffer
---rawDeserialize :: ArrayBuffer -> AnswerMessage
+--rawDeserialize :: ArrayBuffer -> AuthDAnswerMessage
 
 data DecodeError
   = JSONERROR CA.JsonDecodeError
   | UnknownNumber
 
-decodeAnswer :: Int -> J.Json -> Either DecodeError AnswerMessage
-decodeAnswer number json
+decodeAuthDAnswer :: Int -> J.Json -> Either DecodeError AuthDAnswerMessage
+decodeAuthDAnswer number json
   = case number of
-    -- TODO: take right values
-    11 -> case (CA.decode token_codec json) of
-      (Left err) -> Left (JSONERROR err)
-      (Right v)  -> Right (Logged v)
-    _ -> Left UnknownNumber
+    0  -> error_management authd_codec_error AuthenticationDaemonError
+    10 -> error_management authd_codec_token Logged
+    12 -> error_management authd_codec_contacts Contact
+    _  -> Left UnknownNumber
+  where
+    -- Signature is required since the compiler's guess is wrong.
+    error_management :: forall a. CA.JsonCodec a -> (a -> AuthDAnswerMessage) -> Either DecodeError AuthDAnswerMessage
+    error_management codec f
+      = case (CA.decode codec json) of
+          (Left err) -> Left (JSONERROR err)
+          (Right v)  -> Right (f v)