diff --git a/core/jsonArg.h b/core/jsonArg.h
index 8fd1be72..398178b6 100644
--- a/core/jsonArg.h
+++ b/core/jsonArg.h
@@ -31,7 +31,13 @@
 #include <iostream>
 
 string arg2json(const AmArg &a);
+
+/** @return true on success */
 bool json2arg(std::istream& input, AmArg& res);
+
+/** @return true on success */
 bool json2arg(const char* input, AmArg& res);
+
+/** @return true on success */
 bool json2arg(const std::string& input, AmArg& res);
 #endif
diff --git a/core/jsonxx.cpp b/core/jsonxx.cpp
index cddb572e..9802152a 100644
--- a/core/jsonxx.cpp
+++ b/core/jsonxx.cpp
@@ -1,4 +1,31 @@
 // Author: Hong Jiang <hong@hjiang.net>
+/* 
+source: http://github.com/hjiang/jsonxx/
+
+Copyright (c) 2010 Hong Jiang
+
+Permission is hereby granted, free of charge, to any person
+obtaining a copy of this software and associated documentation
+files (the "Software"), to deal in the Software without
+restriction, including without limitation the rights to use,
+copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+OTHER DEALINGS IN THE SOFTWARE.
+
+*/
 
 #include "jsonxx.h"
 
diff --git a/core/jsonxx.h b/core/jsonxx.h
index b1fcf7bb..8f716aaf 100644
--- a/core/jsonxx.h
+++ b/core/jsonxx.h
@@ -1,4 +1,31 @@
 // Author: Hong Jiang <hong@hjiang.net>
+/* 
+source: http://github.com/hjiang/jsonxx/
+
+Copyright (c) 2010 Hong Jiang
+
+Permission is hereby granted, free of charge, to any person
+obtaining a copy of this software and associated documentation
+files (the "Software"), to deal in the Software without
+restriction, including without limitation the rights to use,
+copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+OTHER DEALINGS IN THE SOFTWARE.
+
+*/
 
 #include <cassert>
 #include <iostream>