diff --git a/CalamityCommands/CommandUtils.hs b/CalamityCommands/CommandUtils.hs
--- a/CalamityCommands/CommandUtils.hs
+++ b/CalamityCommands/CommandUtils.hs
@@ -116,7 +116,7 @@
   P.Sem r (Command m c a)
 buildCommand names parent hidden checks help command =
   let (parser, cb) = buildTypedCommand @ps command
-   in buildCommand' names parent hidden checks (parameterInfos @ps @r) help parser cb
+   in buildCommand' names parent hidden checks (parameterInfos @ps @c @r) help parser cb
 
 {- | Given the name of the command the parser is for and a parser function in
  the 'P.Sem' monad, build a parser by transforming the Polysemy action into an
@@ -164,7 +164,7 @@
   ( ApplyTupRes (ParserResult (ListToTup ps)) (CommandSemType r a) ~ CommandForParsers ps r a
   , ParameterParser (ListToTup ps) c r
   , ApplyTup (ParserResult (ListToTup ps)) (CommandSemType r a)
-  , ParameterInfoForParsers ps r
+  , ParameterInfoForParsers ps c r
   )
 
 buildTypedCommand ::
@@ -179,14 +179,14 @@
       consumer (ctx, r) = applyTup (cmd ctx) r
    in (parser, consumer)
 
-class ParameterInfoForParsers (ps :: [Type]) r where
+class ParameterInfoForParsers (ps :: [Type]) c r where
   parameterInfos :: [ParameterInfo]
 
-instance ParameterInfoForParsers '[] r where
+instance ParameterInfoForParsers '[] c r where
   parameterInfos = []
 
-instance (ParameterParser x c r, ParameterInfoForParsers xs r) => ParameterInfoForParsers (x : xs) r where
-  parameterInfos = parameterInfo @x @c @r : parameterInfos @xs @r
+instance (ParameterParser x c r, ParameterInfoForParsers xs c r) => ParameterInfoForParsers (x : xs) c r where
+  parameterInfos = parameterInfo @x @c @r : parameterInfos @xs @c @r
 
 class ApplyTup a b where
   type ApplyTupRes a b
diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,5 +1,10 @@
 # Changelog for Calamity Commands
 
+## 0.1.3.0
+
++ Fixed some parameter parser instances causing type inference to fail
+  ([#48](https://github.com/simmsb/calamity/pull/48)).
+
 ## 0.1.2.0
 
 + Changed the command parameter machinery to hold more info about parameters.
diff --git a/calamity-commands.cabal b/calamity-commands.cabal
--- a/calamity-commands.cabal
+++ b/calamity-commands.cabal
@@ -4,10 +4,10 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 962098e7be30e39345aaa5a511635824c3654c1f199212a575271f3d7e6f5c60
+-- hash: ec3fda8daa0c65a69c2b8cfae6a5cb025d8069ab3fe541918c0d14456fa3143b
 
 name:           calamity-commands
-version:        0.1.2.0
+version:        0.1.3.0
 synopsis:       A library for declaring, parsing, and invoking text-input based commands
 description:    Please see the README on GitHub at <https://github.com/simmsb/calamity#readme>
 category:       Utils