> ## 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.

# Create SIP Trunk

> Use the create_sip_trunk MCP tool on the DialNexa remote MCP server.

<span data-api-safety-label="changes-state"><Badge color="yellow" size="sm" shape="pill">Changes state - verify before retry</Badge></span>

Links an organization-owned SIP trunk phone number for outbound/inbound calling. This is NOT a read-only action. Only call this after the user has provided real SIP termination details — never as a guess or with placeholder values.

## Parameters

| Name                 | Type     | Required | Description                                                                      |
| -------------------- | -------- | -------- | -------------------------------------------------------------------------------- |
| `phone_number`       | `string` | Yes      | E.164 phone number, e.g. +14155552671                                            |
| `termination_uri`    | `string` | Yes      | SIP termination host\[:port], e.g. example.zt.provider.com:5060 — no sip: prefix |
| `sip_trunk_username` | `string` | No       | SIP authentication username                                                      |
| `sip_trunk_password` | `string` | No       | SIP authentication password (stored encrypted)                                   |
| `nickname`           | `string` | No       | Display nickname for this trunk                                                  |

## Before you call

* Connect and initialize the MCP client with OAuth or an API key for the intended workspace.
* Provide the required parameters: `phone_number`, `termination_uri`.

## Example MCP request

Send `tools/call` after your client completes MCP initialization. Replace placeholder values with IDs and inputs from your workspace. For object and array parameters, follow the nested requirements in the parameter description instead of treating an empty value as complete.

```json theme={null}
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "create_sip_trunk",
    "arguments": {
      "phone_number": "+919876543210",
      "termination_uri": "VALUE"
    }
  }
}
```

The server returns one text content block. Parse `content[0].text` as JSON when the tool succeeds. See [MCP responses and errors](/docs/mcp-tools/errors) for the full envelope and failure behavior.

## Verify the result

Confirm the response is not marked `isError`. Call [List Organization Phone Numbers](/docs/mcp-tools/phone-numbers/list-organization-phone-numbers) to read the affected resource. Verify that the intended state is visible before making another change.

## Retry safety

This tool changes workspace state. After a timeout, read the affected resource before retrying so you do not create duplicate or conflicting changes.

## Related MCP tools

* [List Organization Phone Numbers](/docs/mcp-tools/phone-numbers/list-organization-phone-numbers): `list_organization_phone_numbers`

## Related guides

* [Connect to the DialNexa MCP server](/docs/mcp-tools/overview)
* [Phone Numbers MCP tools](/docs/mcp-tools/phone-numbers/overview)
* [MCP responses and errors](/docs/mcp-tools/errors)