Answer a survey question

POST/questions/:questionId/answer

Submit or update an answer to a survey question after registering. An existing answer is overwritten.

Auth	Login required

Path parameters

questionIdstringrequired

Question ID.

Request body

answerstring[]required

The answer as a non-empty array of strings, each up to 1000 characters. For choice questions, pass the option IDs.

Request
curl https://api.4s.link/questions/QUESTION_ID/answer \
  -X POST \
  -H "Authorization: Bearer 4s_at_..." \
  -H "Content-Type: application/json" \
  -d '{
  "answer": "情報収集のため"
}'

Example response
{
  "id": "qa1a2b3-...",
  "questionId": "q1a2b3c4-...",
  "answer": "情報収集のため",
  "updatedAt": "2026-08-18T00:00:00.000Z"
}