HTTP output plugin clarification

[nxns1]

Hi, Im sending a json format input to logstash, and I have it configured to post to a http endpoint. When I output the data on stdout I get something like:
{
"path" => "blabla",
"@timestamp" => blabla,
"host" => "blabla",
"message" => "blabla",
"@version" => "1"
}

I was wondering if it's only the message that gets send to the http endpoint, or this whole string? I want to know because I get an http error 400, and I am trying to figure out if it's the bad format of the string. (I only need whats inside the message field)

[Badger]

The default codec on an http output is https://www.elastic.co/guide/en/logstash/7.4/plugins-codecs-plain.html. If you do not specify a format then it will use the timestamp, hostname, and [message] field concatenated.