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

# DialNexa Limits Reference

> Review DialNexa limits and guardrails for phone numbers, webhook URLs, retry counts, webhook timeouts, call settings, custom function timeout, CSV uploads, and version state.

DialNexa limits and guardrails protect users from invalid configuration. Some limits are visible in the dashboard, such as webhook URL length, retry count, webhook timeout, phone number validation, silence timeout, max call duration, and published-version edit locking.

<Warning>
  Limits are not suggestions. They are the product telling you where the edge is before the edge becomes support work.
</Warning>

## Dashboard-Visible Limits

These limits are enforced or surfaced in current product flows.

| Area                          | Limit or guardrail                                                 |
| ----------------------------- | ------------------------------------------------------------------ |
| External webhook URL          | Must start with `https://` and be 150 characters or less.          |
| External webhook retry count  | 0 to 3.                                                            |
| External webhook timeout      | 1,000 ms to 60,000 ms.                                             |
| Phone test recipient          | Validated against selected country code and expected digit length. |
| End call on silence           | Dashboard slider uses 15 to 30 seconds.                            |
| Maximum call duration         | Dashboard slider uses 1 to 90 minutes.                             |
| Custom function timeout       | Default reducer value is `120000` ms.                              |
| Batch and campaign CSV upload | CSV or Excel, maximum 10 MB per file.                              |
| Published agent version       | Many settings are disabled when viewing a published version.       |

## Limit Questions

<AccordionGroup>
  <Accordion title="Why does the UI reject my webhook URL?">
    Use HTTPS and keep it within the character limit.
  </Accordion>

  <Accordion title="Why can I not edit a setting?">
    You may be viewing a published version.
  </Accordion>

  <Accordion title="Why is my phone number rejected?">
    Check country and local digit count.
  </Accordion>

  <Accordion title="Why is upload rejected?">
    Files must be CSV or Excel and at most 10 MB. If the file type and size are fine, check the headers against the downloaded template. See [Common Upload Errors](/batch-calls/common-upload-errors).
  </Accordion>
</AccordionGroup>

## Related Reading

<CardGroup cols={2}>
  <Card title="External Webhooks" icon="webhook" href="/api-access/external-webhooks">
    See webhook validation.
  </Card>

  <Card title="Call Settings" icon="phone" href="/agent-settings/call-settings">
    Review timing controls.
  </Card>

  <Card title="Common Upload Errors" icon="alert-triangle" href="/batch-calls/common-upload-errors">
    Fix CSV issues.
  </Card>
</CardGroup>