> ## Documentation Index
> Fetch the complete documentation index at: https://docs.getversive.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Create question logic

> Add a branching rule to a question

Creates a logic rule. Rules on a question are evaluated top to bottom; the first match wins. Returns `201`.

<ParamField body="study_id" type="string" required>The study.</ParamField>
<ParamField body="question_id" type="string" required>The question the rule attaches to (must belong to the study).</ParamField>

<ParamField body="operation" type="string" required>
  `==`, `<`, `<=`, `>`, `>=`, `COUNT_LT`, `INCLUDES`, `ALWAYS`, or `SMART_CONDITION`. (`INCLUDE_RESPONSE_IN_NEXT_QUESTION` is accepted for backwards compatibility but is legacy — use question mentions instead.)
</ParamField>

<ParamField body="comparison_value_type" type="string" required>
  `string`, `int`, or `smart_condition`.
</ParamField>

<ParamField body="action_type" type="string" required>
  `next_question_id`, `move_to_question_group`, `end_interview`, `redirect_url`, or `screen_out`.
</ParamField>

<ParamField body="comparison_value" type="string">
  The comparison value — or, for `SMART_CONDITION`, the natural-language condition (e.g. "the participant mentions pricing").
</ParamField>

<ParamField body="next_question_id" type="string">
  Required for `next_question_id` actions; must be a question in the same study. Cannot be the rule's own question, or a question inside a randomized group (directly or nested) — target the group with `move_to_question_group` instead.
</ParamField>

<ParamField body="next_question_group_id" type="string">
  Required for `move_to_question_group` actions; the interview enters at the group's first question (respecting per-participant randomization). Question groups must be enabled for the study. Must be a group in the same study that contains at least one question. Cannot be the question's own group or an ancestor of it, or a group nested inside a randomized group.
</ParamField>

<ParamField body="redirect_url" type="string">Required for `redirect_url` actions.</ParamField>
<ParamField body="end_interview" type="boolean" default="false">Set for `end_interview` actions.</ParamField>
<ParamField body="language" type="string" default="English">The language this rule applies to.</ParamField>

### Response

The created logic rule — same shape as [List question logic](/api-reference/question-logic/list-question-logic).

<RequestExample>
  ```bash cURL theme={null}
  curl -X POST https://api.getversive.com/api/v1/question-logic \
    -H "Authorization: Bearer $VERSIVE_API_KEY" \
    -H "Content-Type: application/json" \
    -d '{
      "study_id": "9b2f7c1e-4a4b-4f6e-9a1d-1c2d3e4f5a6b",
      "question_id": "q-123",
      "operation": "<",
      "comparison_value": "3",
      "comparison_value_type": "int",
      "action_type": "screen_out"
    }'
  ```
</RequestExample>