> ## 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 `. 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` from the Node SDK (`@trycourier/courier` v7 and later, where the client is the default import). 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. # SMS providers > Every SMS provider Courier supports, the phone_number profile field, and per-send overrides. export const Endpoint = ({method, path, name, href, children, bare}) => { const verb = String(method || "").toUpperCase(); const title = verb + " " + path; const label = children || name || path; if (bare) { return href ? {title} : {title}; } if (!href) { return {label} {verb} ; } return {label} {verb} ; }; export const Doc = ({href, children, name, bare}) => { const label = children || name || href; if (bare) { return {label}; } return {label} DOC ; }; ## Available providers Amazon SNS also sends push. Twilio is the only one here that carries MMS. ## Profile requirements Every SMS provider addresses the recipient the same way, by phone number, so the profile you send to needs a `phone_number`. Store it once with , which merges into the profile and creates it if it does not exist: ```javascript Node.js highlight={3} theme={null} const profile = await client.profiles.create('user_123', { profile: { phone_number: '+15551234567', }, }); ``` ```python Python highlight={4} theme={null} profile = client.profiles.create( user_id="user_123", profile={ "phone_number": "+15551234567", }, ) ``` ```bash cURL highlight={7} theme={null} curl --request POST \ --url https://api.courier.com/profiles/user_123 \ --header "Authorization: Bearer $COURIER_API_KEY" \ --header 'Content-Type: application/json' \ --data '{ "profile": { "phone_number": "+15551234567" } }' ``` ```ruby Ruby highlight={4} theme={null} profile = courier.profiles.create( "user_123", profile: { phone_number: "+15551234567" } ) ``` ```go Go highlight={6} theme={null} profile, err := client.Profiles.New( context.TODO(), "user_123", courier.ProfileNewParams{ Profile: map[string]any{ "phone_number": "+15551234567", }, }, ) ``` ```java Java highlight={4} theme={null} ProfileCreateParams params = ProfileCreateParams.builder() .userId("user_123") .profile(ProfileCreateParams.Profile.builder() .putAdditionalProperty("phone_number", JsonValue.from("+15551234567")) .build()) .build(); ProfileCreateResponse profile = client.profiles().create(params); ``` ```php PHP highlight={2} theme={null} $profile = $client->profiles->create('user_123', profile: [ 'phone_number' => '+15551234567', ]); ``` ```csharp C# highlight={6} theme={null} ProfileCreateParams parameters = new() { UserID = "user_123", Profile = new Dictionary() { { "phone_number", JsonSerializer.SerializeToElement("+15551234567") }, }, }; var profile = await client.Profiles.Create(parameters); ``` ```bash CLI highlight={4} theme={null} courier profiles create \ --api-key "$COURIER_API_KEY" \ --user-id user_123 \ --profile '{"phone_number":"+15551234567"}' ``` ```text MCP theme={null} With Courier MCP, create a profile for user_123 with the phone number +15551234567. ``` Store the number in E.164 form, with the country code and a leading `+`. A provider that accepts a local format at its own API does not change what Courier stores, and a number without a country code fails at the provider rather than at the send. ## Send to a recipient Courier reads `phone_number` off the saved profile, so preferences apply and the number can change without touching this code. ```javascript Node.js highlight={4} theme={null} const { requestId } = await courier.send.message({ message: { to: { user_id: "user_123", }, template: "nt_01kx4h2jdafq8bk9aftxak4b40", }, }); ``` ```python Python highlight={4} theme={null} response = client.send.message( message={ "to": { "user_id": "user_123", }, "template": "nt_01kx4h2jdafq8bk9aftxak4b40", }, ) ``` ```bash cURL highlight={7} wrap theme={null} 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" } }' ``` ```ruby Ruby highlight={4} theme={null} response = courier.send_.message( message: { to: { user_id: "user_123" }, template: "nt_01kx4h2jdafq8bk9aftxak4b40" } ) ``` ```go Go highlight={5} theme={null} 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"), }, }) ``` ```java Java highlight={3} theme={null} SendMessageParams params = SendMessageParams.builder() .message(SendMessageParams.Message.builder() .to(UserRecipient.builder().userId("user_123").build()) .template("nt_01kx4h2jdafq8bk9aftxak4b40") .build()) .build(); SendMessageResponse response = client.send().message(params); ``` ```php PHP highlight={4} theme={null} $response = $client->send->message( message: [ 'to' => [ 'user_id' => 'user_123', ], 'template' => 'nt_01kx4h2jdafq8bk9aftxak4b40', ], ); ``` ```csharp C# highlight={5} theme={null} SendMessageParams parameters = new() { Message = new() { To = new UserRecipient { UserID = "user_123" }, Template = "nt_01kx4h2jdafq8bk9aftxak4b40", }, }; var response = await client.Send.Message(parameters); ``` ```bash CLI highlight={3} wrap theme={null} courier send message \ --api-key "$COURIER_API_KEY" \ --message.to '{"user_id": "user_123"}' \ --message.template nt_01kx4h2jdafq8bk9aftxak4b40 ``` ```text MCP theme={null} With Courier MCP, send my template to user_123 by SMS. ``` A one-off to a number you are not storing. No profile is created, so no preference applies. ```javascript Node.js highlight={4} theme={null} const { requestId } = await courier.send.message({ message: { to: { phone_number: "+15551234567", }, template: "nt_01kx4h2jdafq8bk9aftxak4b40", }, }); ``` ```python Python highlight={4} theme={null} response = client.send.message( message={ "to": { "phone_number": "+15551234567", }, "template": "nt_01kx4h2jdafq8bk9aftxak4b40", }, ) ``` ```bash cURL highlight={7} wrap theme={null} curl -X POST https://api.courier.com/send \ -H "Authorization: Bearer $COURIER_API_KEY" \ -H "Content-Type: application/json" \ -d '{ "message": { "to": { "phone_number": "+15551234567" }, "template": "nt_01kx4h2jdafq8bk9aftxak4b40" } }' ``` ```ruby Ruby highlight={4} theme={null} response = courier.send_.message( message: { to: { phone_number: "+15551234567" }, template: "nt_01kx4h2jdafq8bk9aftxak4b40" } ) ``` ```go Go highlight={5} theme={null} response, err := client.Send.Message(context.TODO(), courier.SendMessageParams{ Message: courier.SendMessageParamsMessage{ To: courier.SendMessageParamsMessageToUnion{ OfUserRecipient: &shared.UserRecipientParam{ PhoneNumber: courier.String("+15551234567"), }, }, Template: courier.String("nt_01kx4h2jdafq8bk9aftxak4b40"), }, }) ``` ```java Java highlight={3} theme={null} SendMessageParams params = SendMessageParams.builder() .message(SendMessageParams.Message.builder() .to(UserRecipient.builder().phoneNumber("+15551234567").build()) .template("nt_01kx4h2jdafq8bk9aftxak4b40") .build()) .build(); SendMessageResponse response = client.send().message(params); ``` ```php PHP highlight={4} theme={null} $response = $client->send->message( message: [ 'to' => [ 'phone_number' => '+15551234567', ], 'template' => 'nt_01kx4h2jdafq8bk9aftxak4b40', ], ); ``` ```csharp C# highlight={5} theme={null} SendMessageParams parameters = new() { Message = new() { To = new UserRecipient { PhoneNumber = "+15551234567" }, Template = "nt_01kx4h2jdafq8bk9aftxak4b40", }, }; var response = await client.Send.Message(parameters); ``` ```bash CLI highlight={3} wrap theme={null} courier send message \ --api-key "$COURIER_API_KEY" \ --message.to '{"phone_number": "+15551234567"}' \ --message.template nt_01kx4h2jdafq8bk9aftxak4b40 ``` ```text MCP theme={null} With Courier MCP, send my template to +15551234567 by SMS. ``` ## Channel overrides How overrides work covers the two levels and which one wins. Most SMS providers accept these two in a provider override. | Field | Sets | | :------- | :------------------------------------------------------------------- | | `body` | The message text, the recipient number, or other request body fields | | `config` | Credentials or sender numbers, swapped for this one send | Each provider page documents its own schema. Can't find a provider? Start a chat or email [support@courier.com](mailto:support@courier.com)