Here it is
The required Body Parameters need to be in a json structure in your request content. It’s a json string you need to build.
You must use json or xml in the request content body always.
See their example
{
"text": "Update Habitica API Documentation - Tasks",
"type": "todo",
"alias": "hab-api-tasks",
"notes": "Update the tasks api on GitHub",
"tags": [
"ed427623-9a69-4aac-9852-13deb9c190c3"
],
"checklist": [
{
"text": "read wiki",
"completed": true
},
{
"text": "write code"
}
],
"priority": 2
}