diff --git a/src/config.py b/src/config.py
index fdee9fc..3d67ff3 100755
--- a/src/config.py
+++ b/src/config.py
@@ -2,7 +2,7 @@
 
 import re,tempfile,shutil
 
-theme_keys=["client.focused",
+config_keys=["client.focused",
             "client.focused_inactive",
             "client.unfocused",
             "client.urgent",
@@ -22,7 +22,7 @@ def extract_config(config_file):
     tmp=tempfile.NamedTemporaryFile(mode="w",delete=False)
     for line in f:
         is_theme_line=False
-        for key in theme_keys:
+        for key in config_keys:
             if contains(".*"+key+"\s",line):
                 is_theme_line=True
         if not(is_theme_line):
@@ -63,45 +63,10 @@ def apply_to_config(tmp_config,theme):
     for key,value in client_theme.items():
         f.write("client."+key+" "+value["border"]+" "+value["background"]+" "+value["text"]+" "+value["indicator"]+" "+safe_get(value,"child_border")+"\n")
     f.close()
-    
+
+
 def apply_theme(config_file,theme):
     tmp=extract_config(config_file)
     apply_to_config(tmp,theme)
     shutil.move(tmp,config_file)
 
-theme={
-    "bar":{
-        "separator": "#666666",
-        "background": "#333333",
-        "statusline": "#bbbbbb",
-        "focused_workspace": { "border":"#888888",
-                               "background": "#dddddd",
-                               "text": "#222222"},
-        "active_workspace":  { "border": "#333333",
-                               "background": "#555555",
-                               "text": "#bbbbbb"},
-        "inactive_workspace": { "border": "#333333",
-                                "background": "#555555",
-                                "text": "#bbbbbb"},
-        "urgent_workspace": { "border": "#2f343a",
-                              "background": "#900000",
-                              "text": "#ffffff"}},
-    "client": {
-        "client.focused":  { "background": "#888888",
-                             "text": "#dddddd",
-                             "indicator": "#222222",
-                             "child_border": "#2e9ef4"},
-        "client.focused_inactive":  { "background": "#333333",
-                                      "text": "#555555",
-                                      "indicator": "#bbbbbb",
-                                      "child_border": "#484e50"},
-        "client.unfocused":  { "background": "#333333",
-                               "text": "#333333",
-                               "indicator": "#888888",
-                               "child_border": "#292d2e"},
-        "client.urgent":  { "background": "#2f343a",
-                            "text": "#900000",
-                            "indicator": "#ffffff",
-                            "child_border": "#900000"}}
-}
-
diff --git a/src/i3-colors.py b/src/i3-colors.py
index 1e367b5..dd13df5 100755
--- a/src/i3-colors.py
+++ b/src/i3-colors.py
@@ -21,9 +21,9 @@ args = args_parser.parse_args()
 
 ##### Apply Theme #####
 loaded_theme=theme.load(args.theme_path)
+config.apply_theme(os.environ["HOME"]+"/.config/i3/config",loaded_theme)
 for meta_key,meta_value in loaded_theme["meta"].items():
     log(meta_value,title=meta_key.title())
-config.apply_theme(os.environ["HOME"]+"/.config/i3/config",loaded_theme)
 if args.restart:
     subprocess.Popen("i3-msg restart".split()) 
 #######################
diff --git a/src/theme.py b/src/theme.py
index d83b6b5..943832c 100644
--- a/src/theme.py
+++ b/src/theme.py
@@ -1,4 +1,4 @@
-import yaml,re
+import yaml,re, sys
 
 def configure(theme):
     if "colors" in theme:
@@ -22,8 +22,27 @@ def configure(theme):
         theme["bar_colors"]=bar_colors
     return(theme)
 
+def validate(theme):
+    abort=lambda msg: sys.exit("Error while loading theme: "+msg)
+    inv_key=lambda key: abort("invalid key \""+key+"\"")
+    for key,value in theme.items():
+        if not(key in ["meta","colors","window_colors","bar_colors"]):
+            inv_key(key)
+        if key=="bar_colors":
+            for key,value in value.items():
+                if not(key in ["separator","background","statusline",
+                               "focused_workspace","active_workspace","inactive_workspace","urgent_workspace"]):
+                    inv_key(key)
+        if key=="window_colors":
+            for key,value in value.items():
+                if not(key in ["focused","focused_inactive","unfocused","urgent","child_border"]):
+                    inv_key(key)
+
+
 def load(theme_file):
     f=open(theme_file,mode="r")
     theme=yaml.load(f,Loader=yaml.FullLoader)
     f.close()
-    return(configure(theme))
+    theme=configure(theme)
+    validate(theme)
+    return(theme)
diff --git a/themes/alphare b/themes/alphare
index 66df78d..8640df3 100644
--- a/themes/alphare
+++ b/themes/alphare
@@ -1,7 +1,8 @@
 # vim: filetype=yaml
 ---
 meta:
-  description: A beige theme by Alphare
+  author: Alphare
+  description: A beige theme
 colors:
   black: '#000000'
   oldlace: '#FDF6E3'
diff --git a/themes/archlinux b/themes/archlinux
index bfad5aa..b386b25 100644
--- a/themes/archlinux
+++ b/themes/archlinux
@@ -2,7 +2,9 @@
 # TODO: use color aliases to make the theme more readable
 ---
 meta:
-  description: 'Archlinux theme by okraits <http://okraits.de>'
+  author: okraits
+  url: http://okraits.de
+  description: 'Archlinux theme'
 window_colors:
   focused:
     border:           '#0088CC'
diff --git a/themes/base16-tomorrow b/themes/base16-tomorrow
index dfab555..6c2fdce 100644
--- a/themes/base16-tomorrow
+++ b/themes/base16-tomorrow
@@ -19,7 +19,9 @@ colors:
     base0F:              '#a3685a'
 
 meta:
-    description:         'Base16 Tomorrow, by Chris Kempson (http://chriskempson.com)'
+    author: Chris Kempson
+    url: http://chriskempson.com
+    description:         'Base16 Tomorrow'
 window_colors:
     focused:
         border:          'base0D'
diff --git a/themes/debian b/themes/debian
index 16a5380..206cc7e 100644
--- a/themes/debian
+++ b/themes/debian
@@ -2,7 +2,8 @@
 # TODO: use color aliases to make the theme more readable
 ---
 meta:
-  description: 'Debian theme by lasers'
+  author: lasers
+  description: 'Debian theme'
 window_colors:
   focused:
     border:           '#d70a53'
diff --git a/themes/deep-purple b/themes/deep-purple
index 7474fa3..ea63c01 100644
--- a/themes/deep-purple
+++ b/themes/deep-purple
@@ -1,7 +1,9 @@
 # vim: filetype=yaml
 ---
 meta:
-  description: 'Inspired by the Purple and Default themes. By jcpst <http://jcpst.com>'
+  author: jcpst
+  url: http://jcpst.com
+  description: 'Inspired by the Purple and Default themes.'
 bar_colors:
   separator: dimgrey
   background: black