From 0d64b1e7f5170758dd2670848d842215515d1a4c Mon Sep 17 00:00:00 2001 From: Chiranjeet Mishra Date: Sat, 5 Sep 2026 17:33:51 +0000 Subject: [PATCH] Document the pay-as-you-go payment-method requirement on the SMS pages Inbound SMS replies run through the Chat API and inherit its billing gate: a pay-as-you-go org needs a saved payment method (and one completed payment during its first 30 days) or the text is received, a session is created, and no reply is ever sent, with nothing shown in the Dashboard. This was only documented under Troubleshooting on chat/quickstart; the two pages an SMS customer actually follows said nothing about it. Adds a Prerequisites bullet and a Warning to chat/sms-chat and a Requirements bullet to phone-numbers/inbound-sms, both linking to the existing troubleshooting table. Co-Authored-By: Claude Opus 5 (1M context) --- fern/chat/sms-chat.mdx | 5 +++++ fern/phone-numbers/inbound-sms.mdx | 1 + 2 files changed, 6 insertions(+) diff --git a/fern/chat/sms-chat.mdx b/fern/chat/sms-chat.mdx index 05dfc937c..b1bbdd07d 100644 --- a/fern/chat/sms-chat.mdx +++ b/fern/chat/sms-chat.mdx @@ -22,8 +22,13 @@ SMS chat requires a **10DLC-approved Twilio number**. Only customers can initiat * A [Vapi account](https://dashboard.vapi.ai/) with an existing assistant * A **10DLC-approved Twilio phone number** (required for assistant responses) +* On pay-as-you-go plans, a **saved payment method** on your organization (see the note below) * Basic understanding of phone number management + +SMS replies are generated by the Chat API and follow its billing requirements. On a pay-as-you-go plan, your organization needs a saved payment method, and during its first 30 days one completed payment, before Vapi replies to a text. Without them the inbound text is received and a session is created, but no reply is sent and the Dashboard shows no error. Voice calls are not affected. See [Chat troubleshooting](/chat/quickstart#troubleshooting) and [Manage billing and credits](/billing/manage-billing-and-credits). + + --- ## Setup Steps diff --git a/fern/phone-numbers/inbound-sms.mdx b/fern/phone-numbers/inbound-sms.mdx index ba0610d82..424ecb48e 100644 --- a/fern/phone-numbers/inbound-sms.mdx +++ b/fern/phone-numbers/inbound-sms.mdx @@ -23,6 +23,7 @@ When enabled, Vapi configures the Twilio Messaging webhook on your number so inb - **Twilio number in the US** - **SMS capability enabled** on that number (in Twilio and in Vapi) - **US-to-US** messaging only +- On pay-as-you-go plans, a **saved payment method** on your organization, and one completed payment during the organization's first 30 days. Without it, inbound texts are received and a session is created, but no reply is sent and no error is shown. See [Chat troubleshooting](/chat/quickstart#troubleshooting). ## Set up from the Dashboard