---
title: "Changes to Send an SMS from an agent's phone number. First message compliance: Your initial SMS to any new contact must include (1) your brand name, (2) opt-in confirmation, and (3) opt-out instructions (e.g., \"Reply STOP to unsubscribe\"). Non-compliant first messages may be silently filtered by carriers."
method: POST
path: "/agentphone/v1/messages"
---

# Changes to Send an SMS from an agent's phone number. First message compliance: Your initial SMS to any new contact must include (1) your brand name, (2) opt-in confirmation, and (3) opt-out instructions (e.g., "Reply STOP to unsubscribe"). Non-compliant first messages may be silently filtered by carriers.

`POST /agentphone/v1/messages`

> Every recorded change to this operation, newest first.

## Timeline

Changed in 1 of 28 revisions.

- **2026-11-08** `857e915717f4`: 1 breaking

## Changes

- **2026-11-08** `857e915717f4`: 1 breaking
  - added required request body

---

[Operation](https://skmtc.dev/orthogonal/apis/orthogonal-api-marketplace/docs/agentphone/v1/messages/post.md) - [API](https://skmtc.dev/orthogonal/apis/orthogonal-api-marketplace.md) - [Page](https://skmtc.dev/orthogonal/apis/orthogonal-api-marketplace/changes/agentphone/v1/messages/post)