docs: different default for format on osm.org

Add a note that the format parameter is needed for
nominatim.openstreetmap.org for historical reasons.

diff --git a/docs/api/Search.md b/docs/api/Search.md
index 45606a71a1ddd26fd2abd36a8ff8eda969332e92..ce081cab8a1df4b6879d9f8386b55dfc53b97033 100644 (file)
--- a/docs/api/Search.md
+++ b/docs/api/Search.md
@@ -51,6 +51,12 @@ Both query forms accept the additional parameters listed below.
 
 See [Place Output Formats](Output.md) for details on each format. (Default: jsonv2)
 
+!!! note
+    The Nominatim service at
+    [https://nominatim.openstreetmap.org](https://nominatim.openstreetmap.org)
+    has a different default behaviour for historical reasons. When the
+    `format` parameter is omitted, the request will be forwarded to the Web UI.
+
 * `json_callback=<string>`
 
 Wrap JSON output in a callback function ([JSONP](https://en.wikipedia.org/wiki/JSONP)) i.e. `<string>(<json>)`.