Build on ConnectSMS with Flow, Apex, REST and agents.

• Request, then dispatch

  A send stores the message in Salesforce and returns at once. A background job hands it to Twilio, so no entry point makes a callout in your transaction.

• The same checks

  Number access, record access in user mode, opt-outs, merge fields and policies apply to every caller, and are checked again at dispatch.

• Errors are returned, not thrown

  Business problems come back with success = false, a stable errorCode and a plain-language errorMessage. Only unexpected failures throw, with a support reference.

• Idempotent by design

  Pass an idempotencyKey and a repeat returns the original message with duplicate = true instead of sending twice.

• Asynchronous status

  Poll Get Text Message Status until isFinal is true, or subscribe to the content-free platform event csms__ConnectSMS_Update__e.

• Additive versioning

  Global classes, methods and variables are never removed or renamed, and error codes never change. New capabilities arrive as new optional inputs, outputs, actions and methods.

csms.ConnectSMSApi.SendRequest r = new csms.ConnectSMSApi.SendRequest();
r.recordId = appointment.Contact__c;
r.templateId = reminderTemplateId;
r.scheduledAt = appointment.Start__c.addHours(-24);
r.idempotencyKey = appointment.Id + '-reminder-1';
csms.ConnectSMSApi.SendResult result = csms.ConnectSMSApi.send(new List<csms.ConnectSMSApi.SendRequest>{ r })[0];
// result.status is Scheduled; keep result.messageId

// Later, if the appointment is canceled:
csms.ConnectSMSApi.CancelResult canceled = csms.ConnectSMSApi.cancel(result.messageId);
// canceled.errorCode: NOT_CANCELLABLE once the message was handed to Twilio

csms.ConnectSMSApi.PreviewResult preview = csms.ConnectSMSApi.preview(req);
if (!preview.canSend) {
  for (csms.ConnectSMSApi.Issue blocker : preview.blockers) {
    System.debug(blocker.code + ': ' + blocker.message);
  }
}
// preview.renderedBody, preview.characters, preview.segments, preview.encoding (GSM-7 or UCS-2)

List<csms.ConnectSMSApi.MessageStatus> statuses = csms.ConnectSMSApi.getStatus(new List<Id>{ messageId });
csms.ConnectSMSApi.MessageStatus status = statuses[0];
if (status.success && status.isFinal) {
  // Delivered, Undelivered, Failed, Blocked, Canceled, Received or Read
  System.debug(status.displayStatus + ' ' + status.reasonCode + ': ' + status.statusDetail);
}

csms.ConnectSMSApi.ConversationRequest query = new csms.ConnectSMSApi.ConversationRequest();
query.recordId = contactId;
query.pageSize = 20;
csms.ConnectSMSApi.ConversationPage history = csms.ConnectSMSApi.getConversation(query);

if (history.success && history.conversationId != null && !history.optedOut) {
  csms.ConnectSMSApi.ReplyRequest reply = new csms.ConnectSMSApi.ReplyRequest();
  reply.conversationId = history.conversationId;  // always sent from this conversation's number
  reply.body = 'Thanks, we have you down for Friday at 9:00 AM.';
  reply.idempotencyKey = inboundMessageId + '-reply';
  csms.ConnectSMSApi.SendResult sent = csms.ConnectSMSApi.reply(reply);
}

SendRequest

Provide recordId (or toPhone with Campaign Manager or Admin rights) and body or templateId.

SendResult

The other wrapper classes are PreviewResult, Issue, CancelResult, MessageStatus, SenderInfo, ConversationRequest, ConversationMessage, ConversationPage and ReplyRequest. ConnectSMSApi makes no callouts, so it's safe in triggers and after DML. Message bodies returned by getConversation() are untrusted customer content: treat them as data.

ConnectSMS Webhook Guest isn't a role: assign it only to the guest user of the Salesforce Site that receives Twilio webhooks. Administration and access