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The fourth option in the drop-down menu is Forward. This option will forward any SMS message sent to your DID onto the phone number you enter in the text box. Something to note is that it will only forward SMS messages, this does not forward calls.
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Once you create your endpoint and propagation has passed, start sending SMS messages to your DID. You can go back to your webhook endpoint by grabbing the endpoint ID of your URL. The fifth and sixth options are API GET and API POST. Here, you can specify the URL of your webhook or webserver and we will pass SMS messages there. You can also specify an optional Auth Token for authentication.
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To have the previously mentioned URLs fields automatically filled, you can set a default SMS URL. To do this you will need to go to Account -> Settings. Here you will see a textbox that is labeled Default SMS URL. After filling this text box in and clicking the Update Settings button, you will now have the API fields filled in by default with the URL entered.
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