diff --git a/api/prometheus/v1/api.go b/api/prometheus/v1/api.go
index 83b0efee7..b726c81c7 100644
--- a/api/prometheus/v1/api.go
+++ b/api/prometheus/v1/api.go
@@ -824,6 +824,7 @@ type apiOptions struct {
 
 type Option func(c *apiOptions)
 
+// WithTimeout can be used to provide an optional query evaluation timeout for Query and QueryRange.
 func WithTimeout(timeout time.Duration) Option {
 	return func(o *apiOptions) {
 		o.timeout = timeout