diff --git a/docs/api/http.rst b/docs/api/http.rst
index f2a50b27..56b72dc1 100644
--- a/docs/api/http.rst
+++ b/docs/api/http.rst
@@ -25,7 +25,7 @@ to listen to events, you should probably use the WebSocket API instead.
 
 Example usage from the command line::
 
-    $ curl -d '{"jsonrpc": "2.0", "id": 1, "method": "core.playback.get_state"}' http://localhost:6680/mopidy/rpc
+    $ curl -d '{"jsonrpc": "2.0", "id": 1, "method": "core.playback.get_state"}' http://localhost:6680/mopidy/rpc -H 'Content-Type: application/json'
     {"jsonrpc": "2.0", "id": 1, "result": "stopped"}
 
 For details on the request and response format, see :ref:`json-rpc`.