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SMS Tool

Let your agents send text messages to users, customers, or leads. The SMS tool supports multiple providers, works with both chat and voice agents, and is perfect for confirmations, reminders, and follow-ups.

Supported SMS Providers

thinnestAI supports six major SMS providers. Choose the one that fits your region, pricing, and existing infrastructure:

Setting Up the SMS Tool

Step 1: Get Provider Credentials

Sign up with your chosen provider and get your API credentials: Twilio:
Plivo:
Vonage:
Sinch:
Telnyx:
Msg91:

Step 2: Configure the SMS Tool

  1. Navigate to Agents and select your agent.
  2. Go to the Tools section and click Add Tool.
  3. Select SMS.
  4. Choose your SMS provider from the dropdown.
  5. Enter your provider credentials.
  6. Set the From Number — the phone number messages will be sent from.
  7. Save.

Step 3: Assign to an Agent

In your agent’s instructions, tell it when and how to use SMS:

Sending SMS from an Agent

Chat Agent Example

Voice Agent Example

During a voice call, the agent can send an SMS while continuing the conversation:

SMS Mid-Call Actions

One of the most powerful features is sending SMS messages during a live voice call. This allows your voice agent to:
  • Send links — Share URLs that are hard to communicate verbally.
  • Send confirmation details — Booking confirmations, order numbers, reference codes.
  • Send documents — Links to PDFs, contracts, or forms.
  • Send follow-up info — After-call summaries while the conversation is still fresh.

Configuring Mid-Call SMS

  1. Open your voice agent configuration.
  2. In the Tools section, ensure SMS is added and configured.
  3. In the agent instructions, describe when to send texts during calls:

Example: Appointment Reminder with SMS Confirmation

Build a voice agent that books appointments and sends SMS confirmations.

Agent Setup

Agent Instructions

Sample Call

SMS Best Practices

Message Content

  • Keep messages under 160 characters when possible to avoid splitting.
  • Include the business name so recipients know who it’s from.
  • Add a way to opt out or contact you for important/recurring messages.

Compliance

  • Always get consent before sending SMS. Your agent should ask permission.
  • Follow local regulations (TCPA in the US, GDPR in Europe).
  • Include opt-out instructions for marketing messages.
  • Don’t send SMS outside business hours unless it’s time-sensitive.

Deliverability

  • Use a verified phone number with your provider.
  • Register your number for A2P (Application-to-Person) messaging if required.
  • Monitor delivery rates in your provider dashboard.

Troubleshooting

Next Steps