diff --git a/lib/ucoin/hdc/__init__.py b/lib/ucoin/hdc/__init__.py
index fbfe1cd3df612ff8ef2dc2915c6cf2d8a7265681..20495986fdd8b50903fc7f9001b054a4c8c1d9cb 100644
--- a/lib/ucoin/hdc/__init__.py
+++ b/lib/ucoin/hdc/__init__.py
@@ -23,7 +23,7 @@ logger = logging.getLogger("ucoin/hdc")
 
 
 class HDC(API):
-    def __init__(self, module='hdc', server=None, port=None):
+    def __init__(self, server=None, port=None, module='hdc'):
         super().__init__(module, server, port)
 
 from . import amendments, coins, transactions
diff --git a/lib/ucoin/network/__init__.py b/lib/ucoin/network/__init__.py
index 76450488074152af04edb8afda33f4c35f677547..1c849bb5476c9d2e01d3a3cef2e236071f34c6a8 100644
--- a/lib/ucoin/network/__init__.py
+++ b/lib/ucoin/network/__init__.py
@@ -24,7 +24,7 @@ logger = logging.getLogger("ucoin/network")
 
 class Network(API):
     def __init__(self, module='network', server=None, port=None):
-        super().__init__(module, server, port)
+        super().__init__(module=module, server, port)
 
 
 class Pubkey(Network):
diff --git a/lib/ucoin/network/peering/__init__.py b/lib/ucoin/network/peering/__init__.py
index f0ddc3780268534557fc45f9b29d5abeca164cf6..0c8326bdb729b2858fbb26ed75038480cc4ec896 100644
--- a/lib/ucoin/network/peering/__init__.py
+++ b/lib/ucoin/network/peering/__init__.py
@@ -24,7 +24,7 @@ logger = logging.getLogger("ucoin/network/peering")
 
 class Base(Network):
     def __init__(self, server=None, port=None):
-        super().__init__('network/peering', server, port)
+        super().__init__(module='network/peering', server, port)
 
 
 class Peers(Base):
diff --git a/lib/ucoin/pks/__init__.py b/lib/ucoin/pks/__init__.py
index 809acbb7f82f2ee4508feee3f5c02627a829bf13..d13a28a6f09e48c3ed6a93a9a39725569d11f509 100644
--- a/lib/ucoin/pks/__init__.py
+++ b/lib/ucoin/pks/__init__.py
@@ -24,7 +24,7 @@ logger = logging.getLogger("ucoin/pks")
 
 class PKS(API):
     def __init__(self, module='pks', server=None, port=None):
-        super().__init__(module, server, port)
+        super().__init__(module=module, server, port)
 
 
 class Add(PKS):
diff --git a/lib/ucoin/registry/__init__.py b/lib/ucoin/registry/__init__.py
index 1445f929afc55452260d1a982c3db0713398c742..ebb813facaeb8019c799fef6cae82c4d0d23c6b0 100644
--- a/lib/ucoin/registry/__init__.py
+++ b/lib/ucoin/registry/__init__.py
@@ -21,7 +21,7 @@ logger = logging.getLogger("ucoin/registry")
 
 class Registry(API):
     def __init__(self, module='registry', server=None, port=None):
-        super().__init__(module, server, port)
+        super().__init__(module=module, server, port)
 
 
 class Parameters(Registry):