Sending requests to this endpoints to Synapse/Dendrite homeservers leads to some deserialization errors. After claryfing it (https://github.com/matrix-org/matrix-doc/issues/2856), `room_id` and `event_id` fields are expected to appear on request's body and also on path params. It seems that there's some initiative, in any case, to remove the parameters from path: https://github.com/matrix-org/matrix-doc/issues/2330