diff --git a/reverse.md b/reverse.md
index c429512..f4aa38c 100644
--- a/reverse.md
+++ b/reverse.md
@@ -27,6 +27,9 @@ Parameter | Type | Required | Default | Example
 `api_key` | string | yes | none | [get yours here](https://mapzen.com/developers)
 `point.lat` | floating point number | yes | none | `48.858268`
 `point.lon` | floating point number | yes | none | `2.294471`
+`boundary.circle.lat` | floating point number | no | none | `43.818156` 
+`boundary.circle.lon` | floating point number | no | none | `-79.186484` 
+`boundary.circle.radius` | floating point number | no | 1 | `35` 
 `size` | integer | no | `10` | `3`
 `layers` | comma-delimited string array | no | none (all layers) | `address,locality`
 `sources` | comma-delimited string array | no | none (all sources) | `oa,gn`