diff --git a/params.go b/params.go
index 5fe3c2c..12f894c 100644
--- a/params.go
+++ b/params.go
@@ -9,11 +9,15 @@
 	"time"
 )
 
-// MaybeString takes a string that might be a zero-value, and either returns a
-// pointer to its address or a nil value (i.e. empty pointer). This is useful
-// for converting zero values in options structs when the end-user hasn't
-// defined values. Those zero values need to be nil in order for the JSON
-// serialization to ignore them.
+/*
+MaybeString is an internal function to be used by request methods in individual
+resource packages.
+
+It takes a string that might be a zero value and returns either a pointer to its
+address or nil. This is useful for allowing users to conveniently omit values
+from an options struct, but still pass nil to the JSON serializer to omit them
+from a request body.
+*/
 func MaybeString(original string) *string {
 	if original != "" {
 		return &original
@@ -21,8 +25,14 @@
 	return nil
 }
 
-// MaybeInt takes an int that might be a zero-value, and either returns a
-// pointer to its address or a nil value (i.e. empty pointer).
+/*
+MaybeInt is an internal function to be used by request methods in individual
+resource packages.
+
+Like MaybeString, it accepts an int that may be a zero value and returns either
+a pointer to its address or nil to hint to the JSON serializer to omit its
+field.
+*/
 func MaybeInt(original int) *int {
 	if original != 0 {
 		return &original
@@ -61,19 +71,26 @@
 }
 
 /*
-BuildQueryString accepts a generic structure and parses it URL struct. It
-converts field names into query names based on "q" tags. So for example, this
-type:
+BuildQueryString is an internal function to be used by request methods in
+individual resource packages.
 
-	struct {
+It accepts a tagged structure and expands it into a URL struct. Field names are
+converted into query parameters based on a "q" tag. For example:
+
+	type struct Something {
 	   Bar string `q:"x_bar"`
 	   Baz int    `q:"lorem_ipsum"`
-	}{
-	   Bar: "XXX",
-	   Baz: "YYY",
 	}
 
-will be converted into ?x_bar=XXX&lorem_ipsum=YYYY
+	instance := Something{
+	   Bar: "AAA",
+	   Baz: "BBB",
+	}
+
+will be converted into "?x_bar=AAA&lorem_ipsum=BBB".
+
+The struct's fields may be strings, integers, or boolean values. Fields left at
+their type's zero value will be omittted from the query.
 */
 func BuildQueryString(opts interface{}) (*url.URL, error) {
 	optsValue := reflect.ValueOf(opts)
@@ -132,9 +149,34 @@
 	return nil, fmt.Errorf("Options type is not a struct.")
 }
 
-// BuildHeaders accepts a generic structure and parses it into a string map. It
-// converts field names into header names based on "h" tags, and field values
-// into header values by a simple one-to-one mapping.
+/*
+BuildHeaders is an internal function to be used by request methods in
+individual resource packages.
+
+It accepts a arbitrary tagged structure and produces a string map that's
+suitable for use as the HTTP headers of an outgoing request. Field names are
+mapped to header names based in "h" tags.
+
+  type struct Something {
+    Bar string `h:"x_bar"`
+    Baz int    `h:"lorem_ipsum"`
+  }
+
+  instance := Something{
+    Bar: "AAA",
+    Baz: "BBB",
+  }
+
+will be converted into:
+
+  map[string]string{
+    "x_bar": "AAA",
+    "lorem_ipsum": "BBB",
+  }
+
+Untagged fields and fields left at their zero values are skipped. Integers,
+booleans and string values are supported.
+*/
 func BuildHeaders(opts interface{}) (map[string]string, error) {
 	optsValue := reflect.ValueOf(opts)
 	if optsValue.Kind() == reflect.Ptr {