diff --git a/generator.go b/generator.go
index e526e24..e96c14d 100644
--- a/generator.go
+++ b/generator.go
@@ -27,6 +27,10 @@ type GeneratorCallback func(r GeneratorResult)
 func nullCallback(r GeneratorResult) {}
 
 // Generate determines a prime number according to the generator having the specified number of bits
+//
+// In OpenSSL defined generators are 2 and 5. Others are supported but the verification is not possible.
+// The bit size should be adjusted to be high enough for the current requirements. Also you should keep
+// in mind the higher the bitsize, the longer the generation might take.
 func Generate(bits, generator int, cb GeneratorCallback) (*DH, error) {
 	var (
 		err       error