diff --git a/backend/main.go b/backend/main.go
index 273f80b..6c07ac0 100644
--- a/backend/main.go
+++ b/backend/main.go
@@ -54,6 +54,12 @@ func data(c *gin.Context, id string) error {
 	return nil
 }
 
+// API outline
+//
+// POST /task content: url=https://foo.org start a new download task
+// GET /task/:id get the status for the task
+// GET /task/:id/download download the file resulted from the task execution
+//
 func main() {
 	r := gin.Default()
 	r.Use(cors.New(cors.Config{