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

> ## Agent Instructions
> Install the Courier skill before writing code: `npx skills add trycourier/courier-skills`. It carries the verified SDK shapes and the rules you cannot get wrong.
> Authenticate every request with `Authorization: Bearer <API_KEY>`. A workspace has several environments and each has its own keys, which are plain `pk_` strings with no environment prefix. Start with Test.
> Send with `client.send.message`, the default import of the v7 Node SDK. Reference a template by its `nt_` id or its alias.
> A send accepts a bare Elemental element list, but storing content on a template requires the top-level elements wrapped in a channel element.
> Templates and journeys can be built in the Courier app or created through the API. Either way they live in the workspace and are referenced by ID when you send.
> The hosted MCP server is https://mcp.courier.com. For a briefing on what Courier is and when to use it, read https://www.courier.com/llms.txt.
> Prefer the Guides tab for how-do-I questions and the Docs tab for how-does-it-behave questions. The API reference lives under /api-reference.

# Send SMS with SMSCentral through Courier

> Connect SMSCentral with a username and password, then override body and config fields per send.

export const Doc = ({href, children, name, bare}) => {
  const label = children || name || href;
  if (bare) {
    return <a href={href}>{label}</a>;
  }
  return <a className="cx-endpoint" data-kind="doc" href={href}>
      <span className="cx-endpoint-label">{label}</span>
      <span className="cx-endpoint-method">DOC</span>
    </a>;
};

export const AppLink = ({href, children, name, bare}) => {
  const label = children || name || "Open in Courier";
  if (bare) {
    return <a href={href} target="_blank" rel="noreferrer">{label}</a>;
  }
  return <a className="cx-endpoint" data-kind="app" href={href} target="_blank" rel="noreferrer">
      <span className="cx-endpoint-label">{label}</span>
      <span className="cx-endpoint-method" aria-hidden="true">↗</span>
    </a>;
};

## Prerequisites

* [An SMSCentral account](https://www.smscentral.com.au/)
* Your SMSCentral username and password

## Setup

Open the <AppLink href="https://app.courier.com/integrations/catalog/smscentral">SMSCentral Integration</AppLink> in Courier, enter your username and password, then click "Save."

Addressing a recipient and sending are the same on every SMS provider, so they are documented once: <Doc href="/docs/integrations/sms/overview#profile-requirements">profile requirements</Doc> and <Doc href="/docs/integrations/sms/overview#send-to-a-recipient">send to a recipient</Doc>.

## Overrides

<Doc href="/docs/send/overrides#how-overrides-work">How overrides work</Doc> covers the two levels and which one wins.

Overrides change the request body and credentials Courier sends to SMSCentral. Override `username` and `password` via `config`, and `message`, `originator`, and `reference` via `body`.

<CodeGroup>
  ```javascript Node.js highlight={8-20} theme={null}
  const { requestId } = await courier.send.message({
    message: {
      template: "nt_01kx4h2jdafq8bk9aftxak4b40",
      to: {
        phone_number: "+12345678901",
      },
      providers: {
        smscentral: {
          override: {
            body: {
              message: "Override message content",
              originator: "MyCompany",
              reference: "ref-12345",
            },
            config: {
              username: "<override username>",
              password: "<override password>",
            },
          },
        },
      },
    },
  });
  ```

  ```python Python highlight={8-20} theme={null}
  response = client.send.message(
      message={
          "template": "nt_01kx4h2jdafq8bk9aftxak4b40",
          "to": {
              "phone_number": "+12345678901",
          },
          "providers": {
              "smscentral": {
                  "override": {
                      "body": {
                          "message": "Override message content",
                          "originator": "MyCompany",
                          "reference": "ref-12345",
                      },
                      "config": {
                          "username": "<override username>",
                          "password": "<override password>",
                      },
                  },
              },
          },
      },
  )
  ```

  ```bash cURL highlight={11-23} wrap theme={null}
  curl -X POST https://api.courier.com/send \
    -H "Authorization: Bearer $COURIER_API_KEY" \
    -H "Content-Type: application/json" \
    -d '{
      "message": {
        "template": "nt_01kx4h2jdafq8bk9aftxak4b40",
        "to": {
          "phone_number": "+12345678901"
        },
        "providers": {
          "smscentral": {
            "override": {
              "body": {
                "message": "Override message content",
                "originator": "MyCompany",
                "reference": "ref-12345"
              },
              "config": {
                "username": "<override username>",
                "password": "<override password>"
              }
            }
          }
        }
      }
    }'
  ```

  ```ruby Ruby highlight={8-20} theme={null}
  response = courier.send_.message(
    message: {
      template: "nt_01kx4h2jdafq8bk9aftxak4b40",
      to: {
        phone_number: "+12345678901"
      },
      providers: {
        smscentral: {
          override: {
            body: {
              message: "Override message content",
              originator: "MyCompany",
              reference: "ref-12345"
            },
            config: {
              username: "<override username>",
              password: "<override password>"
            }
          }
        }
      }
    }
  )
  ```

  ```go Go highlight={10-22} theme={null}
  response, err := client.Send.Message(context.TODO(), courier.SendMessageParams{
  	Message: courier.SendMessageParamsMessage{
  		To: courier.SendMessageParamsMessageToUnion{
  			OfUserRecipient: &shared.UserRecipientParam{
  				PhoneNumber: courier.String("+12345678901"),
  			},
  		},
  		Template: courier.String("nt_01kx4h2jdafq8bk9aftxak4b40"),
  		Providers: shared.MessageProvidersParam{
  			"smscentral": shared.MessageProvidersTypeParam{
  				Override: map[string]any{
  					"body": map[string]any{
  						"message": "Override message content",
  						"originator": "MyCompany",
  						"reference": "ref-12345",
  					},
  					"config": map[string]any{
  						"username": "<override username>",
  						"password": "<override password>",
  					},
  				},
  			},
  		},
  	},
  })
  ```

  ```java Java highlight={6-16} theme={null}
  SendMessageParams params = SendMessageParams.builder()
      .message(SendMessageParams.Message.builder()
          .to(UserRecipient.builder().phoneNumber("+12345678901").build())
          .template("nt_01kx4h2jdafq8bk9aftxak4b40")
          .providers(MessageProviders.builder()
              .putAdditionalProperty("smscentral", JsonValue.from(java.util.Map.of("override", java.util.Map.of(
                      "body", java.util.Map.of(
                          "message", "Override message content",
                          "originator", "MyCompany",
                          "reference", "ref-12345"
                      ),
                      "config", java.util.Map.of(
                          "username", "<override username>",
                          "password", "<override password>"
                      )
                  ))))
              .build())
          .build())
      .build();
  SendMessageResponse response = client.send().message(params);
  ```

  ```php PHP highlight={8-20} theme={null}
  $response = $client->send->message(
    message: [
      'template' => 'nt_01kx4h2jdafq8bk9aftxak4b40',
      'to' => [
        'phone_number' => '+12345678901',
      ],
      'providers' => [
        'smscentral' => [
          'override' => [
            'body' => [
              'message' => 'Override message content',
              'originator' => 'MyCompany',
              'reference' => 'ref-12345',
            ],
            'config' => [
              'username' => '<override username>',
              'password' => '<override password>',
            ],
          ],
        ],
      ],
    ],
  );
  ```

  ```csharp C# highlight={9-29} theme={null}
  SendMessageParams parameters = new()
  {
      Message = new()
      {
          To = new UserRecipient { PhoneNumber = "+12345678901" },
          Template = "nt_01kx4h2jdafq8bk9aftxak4b40",
          Providers = new Dictionary<string, MessageProvidersType>()
          {
              {
                  "smscentral",
                  new()
                  {
                      Override = JsonSerializer.Deserialize<Dictionary<string, JsonElement>>(
                          """
                          {
                            "body": {
                              "message": "Override message content",
                              "originator": "MyCompany",
                              "reference": "ref-12345"
                            },
                            "config": {
                              "username": "<override username>",
                              "password": "<override password>"
                            }
                          }
                          """
                      ),
                  }
              },
          },
      },
  };

  var response = await client.Send.Message(parameters);
  ```

  ```bash CLI highlight={5} wrap theme={null}
  courier send message \
    --api-key "$COURIER_API_KEY" \
    --message.to '{"phone_number": "+12345678901"}' \
    --message.template nt_01kx4h2jdafq8bk9aftxak4b40 \
    --message.providers '{"smscentral": {"override": {"body": {"message": "Override message content", "originator": "MyCompany", "reference": "ref-12345"}, "config": {"username": "<override username>", "password": "<override password>"}}}}'
  ```

  ```text MCP theme={null}
  With Courier MCP, send my template to +12345678901 through SMSCentral with a different originator.
  ```
</CodeGroup>

SMSCentral does not merge arbitrary fields. Courier reads a fixed set: `override.body.message`, `override.body.reference`, `override.body.originator`, `override.config.username`, and `override.config.password`. Any other field is ignored.

## Provider details

```text theme={null}
smscentral
```

Courier recommends routing to the channel. Naming this key in `routing.channels` instead is supported, and sends through just this provider.

<Card title="Send to a specific provider" icon="bullseye-arrow" href="/docs/send/send-to-a-provider" horizontal arrow="true">
  When that is worth doing, and what you give up: failover, channel priority, and providers you add later.
</Card>