SMS

Text your delegate the same way you’d text a person. It reads your message, thinks about it, and texts you back.

You can have full back-and-forth conversations over SMS, ask questions, give instructions, or just check in — no app needed. Your delegate uses the same Twilio phone number as voice calls, so there’s nothing extra to buy.

Setting up SMS

If you’ve already set up phone calls, you may only need to add one webhook in Twilio. Here’s the full walkthrough:

Step 1 — Check your credentials in Settings

Open Settings in the delegate UI and confirm these fields are filled in (they’ll already be there if you set up phone calls):

  • Twilio Account SID
  • Twilio Auth Token
  • Twilio Phone Number — this is the number you’ll text to and from

Step 2 — Add the SMS webhook in Twilio Console

  1. Log in to console.twilio.com
  2. Go to Phone Numbers → Manage → Active Numbers
  3. Click your number
  4. Scroll to the Messaging section
  5. Under A message comes in, set:
    • Webhook
    • URL: https://<your-delegate-public-url>/sms
    • Method: HTTP POST
  6. Click Save

If you used the same number for phone calls and SMS, this may already be set. Just verify the URL is correct.

Step 3 — (Optional) Set a default SMS number

If you want your delegate to be able to text you proactively — without you texting first — go to Settings and fill in SMS Default To. This is the number your delegate will use when it needs to send you a message on its own initiative (for example, if you asked it to remind you via text about something).

What to expect

Texting your delegate: Send a text to your Twilio number. Your delegate will process it and reply via SMS, usually within a few seconds.

Your delegate texting you: Your delegate has the ability to send you a text at any time — not just in reply to one you sent. For example:

“Remind me via text when the package ships.”

Your delegate will send you an SMS when it has something to tell you, using the number you configured in SMS Default To.

Troubleshooting

  • No reply? Double-check the webhook URL in Twilio Console and make sure your delegate is running and publicly reachable.
  • “Undelivered” in Twilio? Check that your Twilio number has SMS capability enabled.
  • Proactive texts not working? Make sure SMS Default To is set in Settings.

Technical details

  • Inbound SMS handler: src/sms.ts; transient inbound state tracked in src/smsState.ts
  • Webhook route: POST /sms
  • Outbound SMS uses the send_sms tool registered via the local tool provider, calling the Twilio REST API via the twilio npm package
  • If TWILIO_SMS_ACCOUNT_SID / TWILIO_SMS_AUTH_TOKEN are set in Settings, the SMS code uses that account instead of the default voice account — useful if you want to split SMS and voice billing
  • TWILIO_MESSAGING_SERVICE_SID can be set to send via a Twilio Messaging Service instead of a direct number
  • TWILIO_SMS_DEFAULT_TO is the fallback destination number for proactive outbound messages when no destination can be inferred from context

See also: Phone (Twilio) for the broader Twilio account setup.