diff --git a/src/PostgREST/Error.hs b/src/PostgREST/Error.hs
index ac2debbff1..ebb8a7caaf 100644
--- a/src/PostgREST/Error.hs
+++ b/src/PostgREST/Error.hs
@@ -180,22 +180,25 @@ instance JSON.ToJSON ApiRequestError where
     "hint"    .= ("Try changing '" <> child <> "' to one of the following: " <> relHint rels <> ". Find the desired relationship in the 'details' key." :: Text)]
   toJSON (NoRpc schema procName argumentKeys hasPreferSingleObject contentType isInvPost allProcs overloadedProcs)  =
     let func = schema <> "." <> procName
-        prms = "(" <> T.intercalate ", " argumentKeys <> ")"
-        fmtParams =  if null argumentKeys then " function without parameters" else prms <> " function"
+        prms = T.intercalate ", " argumentKeys
+        prmsMsg = "(" <> prms <> ")"
+        prmsDet = " with parameter" <> (if length argumentKeys > 1 then "s " else " ") <> prms
+        fmtPrms p = if null argumentKeys then " without parameters" else p
+        onlySingleParams = hasPreferSingleObject || (isInvPost && contentType `elem` [MTTextPlain, MTTextXML, MTOctetStream])
     in JSON.object [
     "code"    .= SchemaCacheErrorCode02,
-    "message" .= ("Could not find the " <> func <>
+    "message" .= ("Could not find the function " <> func <> (if onlySingleParams then "" else fmtPrms prmsMsg) <> " in the schema cache"),
+    "details" .= ("Searched for the function " <> func <>
       (case (hasPreferSingleObject, isInvPost, contentType) of
-        (True, _, _)                 -> " function with a single json or jsonb parameter"
-        (_, True, MTTextPlain)       -> " function with a single unnamed text parameter"
-        (_, True, MTTextXML)         -> " function with a single unnamed xml parameter"
-        (_, True, MTOctetStream)     -> " function with a single unnamed bytea parameter"
-        (_, True, MTApplicationJSON) -> fmtParams <> " or the " <> func <>" function with a single unnamed json or jsonb parameter"
-        _                            -> fmtParams) <>
-      " in the schema cache"),
-    "details" .= JSON.Null,
+        (True, _, _)                 -> " with a single json/jsonb parameter"
+        (_, True, MTTextPlain)       -> " with a single unnamed text parameter"
+        (_, True, MTTextXML)         -> " with a single unnamed xml parameter"
+        (_, True, MTOctetStream)     -> " with a single unnamed bytea parameter"
+        (_, True, MTApplicationJSON) -> fmtPrms prmsDet <> " or with a single unnamed json/jsonb parameter"
+        _                            -> fmtPrms prmsDet) <>
+      ", but no matches were found in the schema cache."),
     -- The hint will be null in the case of single unnamed parameter functions
-    "hint"    .= if hasPreferSingleObject || (isInvPost && contentType `elem` [MTTextPlain, MTTextXML, MTOctetStream])
+    "hint"    .= if onlySingleParams
                  then Nothing
                  else noRpcHint schema procName argumentKeys allProcs overloadedProcs ]
   toJSON (AmbiguousRpc procs)  = JSON.object [
diff --git a/test/spec/Feature/Query/RpcSpec.hs b/test/spec/Feature/Query/RpcSpec.hs
index b8dfa5ba71..f9275f6625 100644
--- a/test/spec/Feature/Query/RpcSpec.hs
+++ b/test/spec/Feature/Query/RpcSpec.hs
@@ -124,9 +124,9 @@ spec actualPgVersion =
         get "/rpc/sayhell" `shouldRespondWith`
           [json| {
             "hint":"Perhaps you meant to call the function test.sayhello",
-            "message":"Could not find the test.sayhell function without parameters in the schema cache",
+            "message":"Could not find the function test.sayhell without parameters in the schema cache",
             "code":"PGRST202",
-            "details":null} |]
+            "details":"Searched for the function test.sayhell without parameters, but no matches were found in the schema cache."} |]
           { matchStatus  = 404
           , matchHeaders = [matchContentTypeJson]
           }
@@ -139,9 +139,9 @@ spec actualPgVersion =
         get "/rpc/sayhello?nam=Peter" `shouldRespondWith`
           [json| {
             "hint":"Perhaps you meant to call the function test.sayhello(name)",
-            "message":"Could not find the test.sayhello(nam) function in the schema cache",
+            "message":"Could not find the function test.sayhello(nam) in the schema cache",
             "code":"PGRST202",
-            "details":null} |]
+            "details":"Searched for the function test.sayhello with parameter nam, but no matches were found in the schema cache."} |]
           { matchStatus  = 404
           , matchHeaders = [matchContentTypeJson]
           }
@@ -150,9 +150,9 @@ spec actualPgVersion =
         get "/rpc/add_them?a=1&b=2&smthelse=blabla" `shouldRespondWith`
         [json| {
           "hint":"Perhaps you meant to call the function test.add_them(a, b)",
-          "message":"Could not find the test.add_them(a, b, smthelse) function in the schema cache",
+          "message":"Could not find the function test.add_them(a, b, smthelse) in the schema cache",
           "code":"PGRST202",
-          "details":null} |]
+          "details":"Searched for the function test.add_them with parameters a, b, smthelse, but no matches were found in the schema cache."} |]
         { matchStatus  = 404
         , matchHeaders = [matchContentTypeJson]
         }
@@ -164,9 +164,9 @@ spec actualPgVersion =
         `shouldRespondWith`
           [json| {
             "hint":null,
-            "message":"Could not find the test.sayhello function with a single json or jsonb parameter in the schema cache",
+            "message":"Could not find the function test.sayhello in the schema cache",
             "code":"PGRST202",
-            "details":null} |]
+            "details":"Searched for the function test.sayhello with a single json/jsonb parameter, but no matches were found in the schema cache."} |]
         { matchStatus  = 404
         , matchHeaders = [matchContentTypeJson]
         }
@@ -175,18 +175,18 @@ spec actualPgVersion =
         get "/rpc/overloaded?wrong_arg=value" `shouldRespondWith`
           [json| {
             "hint":null,
-            "message":"Could not find the test.overloaded(wrong_arg) function in the schema cache",
+            "message":"Could not find the function test.overloaded(wrong_arg) in the schema cache",
             "code":"PGRST202",
-            "details":null} |]
+            "details":"Searched for the function test.overloaded with parameter wrong_arg, but no matches were found in the schema cache."} |]
           { matchStatus  = 404
           , matchHeaders = [matchContentTypeJson]
           }
         get "/rpc/overloaded?a=1&b=2&wrong_arg=value" `shouldRespondWith`
           [json| {
             "hint":"Perhaps you meant to call the function test.overloaded(a, b, c)",
-            "message":"Could not find the test.overloaded(a, b, wrong_arg) function in the schema cache",
+            "message":"Could not find the function test.overloaded(a, b, wrong_arg) in the schema cache",
             "code":"PGRST202",
-            "details":null} |]
+            "details":"Searched for the function test.overloaded with parameters a, b, wrong_arg, but no matches were found in the schema cache."} |]
           { matchStatus  = 404
           , matchHeaders = [matchContentTypeJson]
           }
@@ -1274,9 +1274,9 @@ spec actualPgVersion =
             `shouldRespondWith`
               [json|{
                 "hint": "Perhaps you meant to call the function test.unnamed_text_param",
-                "message": "Could not find the test.unnamed_int_param(x, y) function or the test.unnamed_int_param function with a single unnamed json or jsonb parameter in the schema cache",
+                "message": "Could not find the function test.unnamed_int_param(x, y) in the schema cache",
                 "code":"PGRST202",
-                "details":null
+                "details":"Searched for the function test.unnamed_int_param with parameters x, y or with a single unnamed json/jsonb parameter, but no matches were found in the schema cache."
               }|]
               { matchStatus  = 404
               , matchHeaders = [ matchContentTypeJson ]
@@ -1289,9 +1289,9 @@ spec actualPgVersion =
             `shouldRespondWith`
               [json|{
                 "hint": null,
-                "message": "Could not find the test.unnamed_int_param function with a single unnamed text parameter in the schema cache",
+                "message": "Could not find the function test.unnamed_int_param in the schema cache",
                 "code":"PGRST202",
-                "details":null
+                "details":"Searched for the function test.unnamed_int_param with a single unnamed text parameter, but no matches were found in the schema cache."
               }|]
               { matchStatus  = 404
               , matchHeaders = [ matchContentTypeJson ]
@@ -1304,9 +1304,9 @@ spec actualPgVersion =
             `shouldRespondWith`
               [json|{
                 "hint": null,
-                "message": "Could not find the test.unnamed_int_param function with a single unnamed xml parameter in the schema cache",
+                "message": "Could not find the function test.unnamed_int_param in the schema cache",
                 "code":"PGRST202",
-                "details":null
+                "details":"Searched for the function test.unnamed_int_param with a single unnamed xml parameter, but no matches were found in the schema cache."
               }|]
               { matchStatus  = 404
               , matchHeaders = [ matchContentTypeJson ]
@@ -1320,9 +1320,9 @@ spec actualPgVersion =
           `shouldRespondWith`
             [json|{
               "hint": null,
-              "message": "Could not find the test.unnamed_int_param function with a single unnamed bytea parameter in the schema cache",
+              "message": "Could not find the function test.unnamed_int_param in the schema cache",
               "code":"PGRST202",
-              "details":null
+              "details":"Searched for the function test.unnamed_int_param with a single unnamed bytea parameter, but no matches were found in the schema cache."
             }|]
             { matchStatus  = 404
             , matchHeaders = [ matchContentTypeJson ]
@@ -1380,9 +1380,9 @@ spec actualPgVersion =
             `shouldRespondWith`
               [json| {
                 "hint":"Perhaps you meant to call the function test.overloaded_unnamed_param(x, y)",
-                "message":"Could not find the test.overloaded_unnamed_param(a, b) function in the schema cache",
+                "message":"Could not find the function test.overloaded_unnamed_param(a, b) in the schema cache",
                 "code":"PGRST202",
-                "details":null
+                "details":"Searched for the function test.overloaded_unnamed_param with parameters a, b, but no matches were found in the schema cache."
               }|]
               { matchStatus  = 404
               , matchHeaders = [matchContentTypeJson]