curl --request POST \
  --url https://app.npcbuilder.com/api/sessionmanager \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{
  "session_key": "campaign_nightfall",
  "game_id": "game_12345",
  "player_id": "550e8400-e29b-41d4-a716-446655440000"
}'

{
  "message": "Session created for key: campaign_nightfall with id: ABC123 has been created",
  "session_key": "<string>",
  "session_id": "<string>",
  "player_id": "<string>"
}