# Conversations, Reactions & More

Published: 2026-03-25

> New conversation threading, message reactions, validation endpoints, URL shortening, and an expanded MCP server.

## Conversations, Reactions & More

New conversation threading, message reactions, validation endpoints, URL shortening, and an expanded MCP server.

### What's new?

**Conversations API**

Messages between a sender and recipient are now grouped into conversation threads — the backbone of inbox-style experiences.

- **List conversations** filtered by brand, campaign, sender, or receiver
- **Get a conversation** by ID or phone number pair
- **List messages** within a conversation with pagination
- **Update conversation notes** for internal tracking

[View API reference →](/api-reference/conversations)

**Message reactions**

React to messages with emoji using [`POST /messages/react`](/api-reference/messages/react). Messages support multiple reactions.

**Message validation**

Validate SMS, MMS, and RCS messages before sending — check segment count, encoding, unsupported files, and estimated cost without consuming credits.

- [`POST /messages/validate/sms`](/api-reference/messages/validate-sms) | [`POST /messages/validate/mms`](/api-reference/messages/validate-mms) | [`POST /messages/validate/rcs`](/api-reference/messages/validate-rcs)

**URL shortener**

Create tracked short links (`pncl.to`) with click analytics, configurable expiration, and updatable destinations.

- [`POST /tools/url`](/api-reference/tools/create-url) | [`GET /tools/url/{linkId}`](/api-reference/tools/get-url)

**MCP Server — 89 tools**

The [Pinnacle MCP server](/mcp) now exposes **89 tools** (up from 71 at launch), covering conversations, webhooks, test agents, and more.

**Note:** Have questions? Reach out to us - founders@pinnacle.sh