---
title: Introduction | API Docs
description: Linq Partner API V2 (Legacy) — overview and feature summary.
---

V2 is legacy

These docs are for our legacy V2 API. If you’re starting a new integration, use the [V3 API](/index.md) instead — see the [Quickstart](/getting-started/quickstart/index.md) to get going in minutes.

## Welcome to the Linq Partner API

The Linq Partner API enables you to integrate iMessage, RCS, and SMS messaging directly into your applications. Build powerful conversational experiences, automate customer communication, and leverage the same messaging infrastructure trusted by 50,000+ teams.

### What you can build

With the Partner API, you can:

- **Send and receive iMessage, RCS, and SMS messages** at scale through your organization’s phone numbers
- **Start and manage group chats** between your app and multiple users
- **Automate conversations** with customers, leads, and team members
- **Receive real-time notifications** via webhooks for incoming messages, reactions, and events
- **Manage contacts** across your organization
- **Track message delivery** with read receipts and delivery status

### Who is this for?

The Partner API is designed for:

- **Software platforms** building messaging into their product
- **CRM and sales tools** adding conversational AI capabilities
- **Customer support platforms** offering multi-channel communication
- **Marketing automation tools** engaging customers via text
- **Developers** building custom messaging solutions

### Key features

#### Unified messaging

Send iMessages and RCS with rich media (images, videos, documents) and automatically fall back to SMS when needed. One API for all three channels.

#### Real-time webhooks

Receive instant notifications when messages arrive, contacts are updated, or users interact with your messages through reactions and typing indicators.

#### Full message features

Access the complete iMessage and RCS feature set:

- Read receipts and typing indicators
- Message reactions (love, like, laugh, etc.)
- Message editing and deletion
- Attachments and rich media
- Group conversations

#### Secure and reliable

All messages are sent through real phone numbers in your organization. Your integration token controls access and determines which phone numbers you can message from.

#### Contact management

Maintain a centralized address book with automatic user assignment and organization-wide visibility.

### Use cases

#### Customer support automation

Build AI-powered support agents that handle customer inquiries via text, with seamless handoff to human agents when needed.

#### Sales engagement

Automate personalized outreach campaigns and follow-ups. Track responses and engagement in real-time.

#### Appointment reminders

Send automated reminders for appointments, meetings, or events with two-way confirmation.

#### Lead qualification

Qualify inbound leads through conversational flows before routing to your sales team.

#### Order notifications

Keep customers informed about order status, shipping updates, and delivery notifications.

### Getting started

Ready to start building? Start with [Authentication](/v2/authentication/index.md) and then send your first message in under 5 minutes via [Your First Message](/v2/your-first-message/index.md). Browse the full endpoint catalog under [V2 Reference](/v2/api/index.md).

Need help? Contact your Linq representative for API token provisioning and technical support.