# Create a topic

Source: https://docs.settlemint.com/docs/user-guides/data-feeds/create-topic
Register a scalar feed verification topic to define the data schema for your data feeds.



A data feed needs a verification topic before operators can register or publish values. Scalar feed topics use the fixed `int256 value` schema and live on the **Verification topics and issuers** page.

## Prerequisites [#prerequisites]

* **Verification policy manager** role (`claimPolicyManager`) assigned on the System Access Manager
* **Issuer-Signed Scalar Feed** addon installed (see [Install addons](/docs/user-guides/system-addons/install-addons))

## Topic kinds [#topic-kinds]

The topic form separates identity verification topics from data feed topics:

| Kind             | Signature                                        | Purpose                                                                  |
| ---------------- | ------------------------------------------------ | ------------------------------------------------------------------------ |
| **Verification** | Custom ABI fields, such as `string` or `uint256` | Identity and compliance verification topics such as KYC or accreditation |
| **Scalar feed**  | `int256 value` (fixed)                           | Numeric data feeds for prices, rates, and metrics                        |
| **Bytes feed**   | Disabled in the topic form                       | Not selectable for the data feed setup workflow                          |

Only **Scalar feed** topics are selectable when creating scalar data feeds. The disabled **Bytes feed** option cannot be used in this workflow.

## Steps [#steps]

<Steps>
  <Step>
    ### Navigate to verification topics and issuers [#navigate-to-verification-topics-and-issuers]

    Go to **Platform Settings** > **Verification topics and issuers** in the sidebar. This page lists registered topics and trusted issuers.

    ![Verification Topics & Issuers page](/docs/data-feeds/verification-topics-list.webp)
  </Step>

  <Step>
    ### Open the add topic form [#open-the-add-topic-form]

    Click **Add verification topic** to open the topic creation dialog.

    ![Add topic form](/docs/data-feeds/add-topic-form.webp)
  </Step>

  <Step>
    ### Select the Scalar feed kind [#select-the-scalar-feed-kind]

    Choose &#x2A;*Feed (SCALAR)** as the topic kind. The signature field locks to `int256 value` and cannot be edited.

    Enter a descriptive **Topic name** that identifies what data this topic represents, such as "FEED: BTC/USD" or "FEED: Interest Rate".

    ![Scalar feed topic configuration](/docs/data-feeds/add-topic-scalar-feed.webp)

    <Callout type="info" title="Naming convention">
      While there is no enforced naming convention, prefixing feed topic names with "FEED:" helps distinguish them from
      compliance verification topics in dropdown lists.
    </Callout>
  </Step>

  <Step>
    ### Confirm the transaction [#confirm-the-transaction]

    Click **Continue** to review the topic kind, topic name, and fixed signature. Then click **Create topic** and complete the wallet verification step.

    ![Topic creation PIN confirmation](/docs/data-feeds/add-topic-confirm.webp)
  </Step>

  <Step>
    ### Verify the topic was created [#verify-the-topic-was-created]

    After the transaction confirms, the new topic appears in the verification topics list. It can then be assigned to a trusted issuer and selected when creating scalar data feeds.
  </Step>
</Steps>

## Next steps [#next-steps]

After creating a topic:

1. **Add a trusted issuer** for this topic so that an identity can publish feed updates. See [Configure trusted issuers](/docs/user-guides/compliance/configure-trusted-issuers).
2. **Create a feed** that uses this topic. See [Create a feed](/docs/user-guides/data-feeds/create-feed).

## Troubleshooting [#troubleshooting]

| Issue                                | Solution                                                                                  |
| ------------------------------------ | ----------------------------------------------------------------------------------------- |
| **Add verification topic** is hidden | Verify you have the **Verification policy manager** role on the System Access Manager     |
| **Feed (SCALAR)** is unavailable     | Ensure the **Issuer-Signed Scalar Feed** addon is installed                               |
| **Feed (BYTES)** cannot be selected  | Use &#x2A;*Feed (SCALAR)** for this workflow; bytes feed topics are not selectable        |
| Topic name already exists            | Choose a unique name; the create transaction rejects duplicate topic names                |
| Transaction fails                    | Check that your wallet can complete the verification step and has enough gas for the call |