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

# Add Selected Skill

> Record that a user has selected a skill.

Send a user ID and a skill ID, and this creates a record tying them together. That's it.

One rule: a user can't select the same skill twice. Try it and you'll get a `409`. This is enforced at both the application level and in the database with a compound unique index, so even concurrent requests won't create duplicates.

No authentication needed.

***

## Request Body

<ParamField body="user_id" type="string" required>
  The user who's selecting the skill.
</ParamField>

<ParamField body="skill_id" type="string" required>
  The skill being selected.
</ParamField>

<ParamField body="sub_skill_id" type="string" required>
  The sub-skill category this skill belongs to. You can get this from the search endpoint.
</ParamField>

<ParamField body="master_skill_id" type="string" required>
  The master skill category. Also available from search results.
</ParamField>

***

## Response

<ResponseField name="success" type="boolean">`true` when the record is created</ResponseField>
<ResponseField name="message" type="string">A short confirmation message</ResponseField>

<ResponseField name="data" type="object">
  The newly created record. Hold onto the `selected_skill_id` — you'll need it if you want to delete this later.

  <Expandable title="The created record">
    <ResponseField name="selected_skill_id" type="string">Auto-generated UUID. Save this.</ResponseField>

    <ResponseField name="user_id" type="string" />

    <ResponseField name="skill_id" type="string" />

    <ResponseField name="sub_skill_id" type="string" />

    <ResponseField name="master_skill_id" type="string" />

    <ResponseField name="createdAt" type="string">ISO 8601 timestamp</ResponseField>
  </Expandable>
</ResponseField>

***

## Examples

<CodeGroup>
  ```bash cURL theme={null}
  curl -X POST http://localhost:5000/api/selected-skills \
    -H "Content-Type: application/json" \
    -d '{
      "user_id": "user-123",
      "skill_id": "sk-001",
      "sub_skill_id": "sub-001",
      "master_skill_id": "ms-001"
    }'
  ```

  ```js JavaScript theme={null}
  const res = await fetch("http://localhost:5000/api/selected-skills", {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({
      user_id: "user-123",
      skill_id: "sk-001",
      sub_skill_id: "sub-001",
      master_skill_id: "ms-001"
    })
  });
  const data = await res.json();
  ```

  ```python Python theme={null}
  import requests

  res = requests.post(
    "http://localhost:5000/api/selected-skills",
    json={
      "user_id": "user-123",
      "skill_id": "sk-001",
      "sub_skill_id": "sub-001",
      "master_skill_id": "ms-001"
    }
  )
  print(res.json())
  ```
</CodeGroup>

<ResponseExample>
  ```json 201 theme={null}
  {
    "success": true,
    "message": "Skill selected successfully",
    "data": {
      "selected_skill_id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
      "user_id": "user-123",
      "skill_id": "sk-001",
      "sub_skill_id": "sub-001",
      "master_skill_id": "ms-001",
      "createdAt": "2025-01-15T10:30:00.000Z",
      "updatedAt": "2025-01-15T10:30:00.000Z"
    }
  }
  ```

  ```json 400 theme={null}
  {
    "message": "\"skill_id\" is required"
  }
  ```

  ```json 409 theme={null}
  {
    "success": false,
    "message": "Skill already selected by this user"
  }
  ```
</ResponseExample>

***

<Info>
  **Why does the 409 check happen twice?**

  The route checks for an existing `{ user_id, skill_id }` record before trying to insert. But just in case two requests land at exactly the same time, the database also has a compound unique index on those fields. The app-level check gives you the nicer error message. The DB-level index is the safety net.
</Info>