Send to a provider

Courier recommends routing to a channel. Naming a provider key in routing.channels instead is supported, and sends through that one provider.

const { requestId } = await courier.send.message({
  message: {
    to: {
      user_id: "user_123",
    },
    template: "nt_01kx4h2jdafq8bk9aftxak4b40",
    routing: {
      method: "single",
      channels: [
        "some-provider-key",
      ],
    },
  },
});

response = client.send.message(
    message={
        "to": {
            "user_id": "user_123",
        },
        "template": "nt_01kx4h2jdafq8bk9aftxak4b40",
        "routing": {
            "method": "single",
            "channels": [
                "some-provider-key",
            ],
        },
    },
)

curl -X POST https://api.courier.com/send \
  -H "Authorization: Bearer $COURIER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "message": {
      "to": {
        "user_id": "user_123"
      },
      "template": "nt_01kx4h2jdafq8bk9aftxak4b40",
      "routing": {
        "method": "single",
        "channels": [
          "some-provider-key"
        ]
      }
    }
  }'

response = courier.send_.message(
  message: {
    to: {
      user_id: "user_123"
    },
    template: "nt_01kx4h2jdafq8bk9aftxak4b40",
    routing: {
      method: "single",
      channels: [
        "some-provider-key"
      ]
    }
  }
)

response, err := client.Send.Message(context.TODO(), courier.SendMessageParams{
	Message: courier.SendMessageParamsMessage{
		To: courier.SendMessageParamsMessageToUnion{
			OfUserRecipient: &shared.UserRecipientParam{
				UserID: courier.String("user_123"),
			},
		},
		Template: courier.String("nt_01kx4h2jdafq8bk9aftxak4b40"),
		Routing: courier.SendMessageParamsMessageRouting{
			Channels: []shared.MessageRoutingChannelUnionParam{
				{OfString: courier.String("some-provider-key")},
			},
			Method: "single",
		},
	},
})

SendMessageParams params = SendMessageParams.builder()
    .message(SendMessageParams.Message.builder()
        .to(UserRecipient.builder().userId("user_123").build())
        .template("nt_01kx4h2jdafq8bk9aftxak4b40")
        .routing(SendMessageParams.Message.Routing.builder()
            .addChannel("some-provider-key")
            .method(SendMessageParams.Message.Routing.Method.SINGLE)
            .build())
        .build())
    .build();
SendMessageResponse response = client.send().message(params);

$response = $client->send->message(
  message: [
    'to' => [
      'user_id' => 'user_123',
    ],
    'template' => 'nt_01kx4h2jdafq8bk9aftxak4b40',
    'routing' => [
      'method' => 'single',
      'channels' => [
        'some-provider-key',
      ],
    ],
  ],
);

SendMessageParams parameters = new()
{
    Message = new()
    {
        To = new UserRecipient { UserID = "user_123" },
        Template = "nt_01kx4h2jdafq8bk9aftxak4b40",
        Routing = new() { Channels = ["some-provider-key"], Method = Send::Method.Single },
    },
};

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

courier send message \
  --api-key "$COURIER_API_KEY" \
  --message.to '{"user_id": "user_123"}' \
  --message.template nt_01kx4h2jdafq8bk9aftxak4b40 \
  --message.routing '{"method": "single", "channels": ["some-provider-key"]}'

With Courier MCP, send my nt_01kx4h2jdafq8bk9aftxak4b40 template to user_123 through some-provider-key only.

Route to the channel first

Routing to a channel is what Courier recommends. Attach your providers to it, address the recipient, and route to the channel by name. Courier then tries that channel’s providers in and moves to the next one when a send fails. A provider you connect later joins the order without a code change. Pin a provider only for the cases below.

When to pin one

Smoke-testing a provider you just connected, before it carries real traffic.
Reproducing one provider’s behavior while you debug a delivery.
Splitting traffic across two providers on the same channel, such as a transactional sender and a bulk sender.

What pinning costs

You give up	Because
Failover	The list holds one provider, so there is nothing to fall back to.
Channel priority	The channel’s provider order no longer decides anything.
Providers added later	The key names one provider, and a new one never becomes a candidate.

A provider key selects, it does not install. Connect the provider under , then add it to the channel in the template’s routing selector. A channel delivers only through the providers attached to it.

Overrides need no pin

A is keyed by provider, and Courier applies it when that provider runs. Route to the channel and the override still lands.

const { requestId } = await courier.send.message({
  message: {
    to: {
      user_id: "user_123",
    },
    template: "nt_01kx4h2jdafq8bk9aftxak4b40",
    routing: {
      method: "single",
      channels: [
        "push",
      ],
    },
    providers: {
      apn: {
        override: {
          body: {
            badge: 99,
          },
        },
      },
    },
  },
});

response = client.send.message(
    message={
        "to": {
            "user_id": "user_123",
        },
        "template": "nt_01kx4h2jdafq8bk9aftxak4b40",
        "routing": {
            "method": "single",
            "channels": [
                "push",
            ],
        },
        "providers": {
            "apn": {
                "override": {
                    "body": {
                        "badge": 99,
                    },
                },
            },
        },
    },
)

curl -X POST https://api.courier.com/send \
  -H "Authorization: Bearer $COURIER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "message": {
      "to": {
        "user_id": "user_123"
      },
      "template": "nt_01kx4h2jdafq8bk9aftxak4b40",
      "routing": {
        "method": "single",
        "channels": [
          "push"
        ]
      },
      "providers": {
        "apn": {
          "override": {
            "body": {
              "badge": 99
            }
          }
        }
      }
    }
  }'

response = courier.send_.message(
  message: {
    to: {
      user_id: "user_123"
    },
    template: "nt_01kx4h2jdafq8bk9aftxak4b40",
    routing: {
      method: "single",
      channels: [
        "push"
      ]
    },
    providers: {
      apn: {
        override: {
          body: {
            badge: 99
          }
        }
      }
    }
  }
)

response, err := client.Send.Message(context.TODO(), courier.SendMessageParams{
	Message: courier.SendMessageParamsMessage{
		To: courier.SendMessageParamsMessageToUnion{
			OfUserRecipient: &shared.UserRecipientParam{
				UserID: courier.String("user_123"),
			},
		},
		Template: courier.String("nt_01kx4h2jdafq8bk9aftxak4b40"),
		Routing: courier.SendMessageParamsMessageRouting{
			Channels: []shared.MessageRoutingChannelUnionParam{
				{OfString: courier.String("push")},
			},
			Method: "single",
		},
		Providers: shared.MessageProvidersParam{
			"apn": shared.MessageProvidersTypeParam{
				Override: map[string]any{
					"body": map[string]any{
						"badge": 99,
					},
				},
			},
		},
	},
})

SendMessageParams params = SendMessageParams.builder()
    .message(SendMessageParams.Message.builder()
        .to(UserRecipient.builder().userId("user_123").build())
        .template("nt_01kx4h2jdafq8bk9aftxak4b40")
        .routing(SendMessageParams.Message.Routing.builder()
            .addChannel("push")
            .method(SendMessageParams.Message.Routing.Method.SINGLE)
            .build())
        .providers(MessageProviders.builder()
            .putAdditionalProperty("apn", JsonValue.from(java.util.Map.of("override", java.util.Map.of(
                    "body", java.util.Map.of("badge", 99)
                ))))
            .build())
        .build())
    .build();
SendMessageResponse response = client.send().message(params);

$response = $client->send->message(
  message: [
    'to' => [
      'user_id' => 'user_123',
    ],
    'template' => 'nt_01kx4h2jdafq8bk9aftxak4b40',
    'routing' => [
      'method' => 'single',
      'channels' => [
        'push',
      ],
    ],
    'providers' => [
      'apn' => [
        'override' => [
          'body' => [
            'badge' => 99,
          ],
        ],
      ],
    ],
  ],
);

SendMessageParams parameters = new()
{
    Message = new()
    {
        To = new UserRecipient { UserID = "user_123" },
        Template = "nt_01kx4h2jdafq8bk9aftxak4b40",
        Routing = new() { Channels = ["push"], Method = Send::Method.Single },
        Providers = new Dictionary<string, MessageProvidersType>()
        {
            {
                "apn",
                new()
                {
                    Override = JsonSerializer.Deserialize<Dictionary<string, JsonElement>>(
                        """{"body": {"badge": 99}}"""
                    ),
                }
            },
        },
    },
};

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

courier send message \
  --api-key "$COURIER_API_KEY" \
  --message.to '{"user_id": "user_123"}' \
  --message.template nt_01kx4h2jdafq8bk9aftxak4b40 \
  --message.routing '{"method": "single", "channels": ["push"]}' \
  --message.providers '{"apn": {"override": {"body": {"badge": 99}}}}'

With Courier MCP, send my nt_01kx4h2jdafq8bk9aftxak4b40 template to user_123 on push with a badge count of 99.

APNs gets the badge. Firebase FCM, on the same channel, is untouched.

Find a provider key

Every provider page ends with a Provider key section carrying the exact string, and lists them all. The key also names each attempt in .

Limits & behavior

A provider key is a supported value, not a workaround. Courier recommends a channel key, and accepts either in the same list.
A pinned provider has no failover. Channel priority and the next-provider fallback both stop applying.
The provider must already be on the template’s channel. A key in routing.channels selects, it does not attach.
providers.<key>.override works without a pin. Route to the channel and the override applies when that provider runs.

Get started

Send messages

Journeys

Broadcasts

Design

Recipients

Tenants

Monitoring

Workspaces

Resources

Send to a provider

Route to the channel first

When to pin one

What pinning costs

Overrides need no pin

Find a provider key

Limits & behavior

​Route to the channel first

​When to pin one

​What pinning costs

​Overrides need no pin

​Find a provider key

​Limits & behavior

Route to the channel first

When to pin one

What pinning costs

Overrides need no pin

Find a provider key

Limits & behavior