Zoom Realtime Media Streams (RTMS)

Background reference for live Zoom media pipelines. Prefer build-zoom-bot first, then use this skill for stream types, capabilities, and RTMS-specific implementation constraints.

Zoom Realtime Media Streams (RTMS)

Expert guidance for accessing live audio, video, transcript, chat, and screen share data from Zoom meetings, webinars, Video SDK sessions, and Zoom Contact Center Voice in real-time. RTMS uses a WebSocket-based protocol with open standards and does not require a meeting bot to capture the media plane.

Read This First (Critical)

RTMS is primarily a backend media ingestion service.

• Your backend receives and processes live media: audio, video, screen share, chat, transcript.

• RTMS is not a frontend UI SDK by itself.

• Processing is event-triggered: backend waits for RTMS start webhook events before stream handling begins.

Optional architecture (common):

• Add a Zoom App SDK frontend for in-client UI/controls.

• Stream backend RTMS outputs to frontend via WebSocket (or SSE, gRPC, queue workers, etc.).

Use RTMS for media/data plane, and use frontend frameworks/Zoom Apps for presentation + user interactions.

Official Documentation: https://developers.zoom.us/docs/rtms/ SDK Reference (JS): https://zoom.github.io/rtms/js/ SDK Reference (Python): https://zoom.github.io/rtms/py/ Sample Repository: https://github.com/zoom/rtms-samples

Quick Links

New to RTMS? Follow this path:

• Connection Architecture - Two-phase WebSocket design

• SDK Quickstart - Fastest way to receive media (recommended)

• Manual WebSocket - Full protocol control without SDK

• Media Types - Audio, video, transcript, chat, screen share

Complete Implementation:

• RTMS Bot - End-to-end bot implementation guide

Reference:

• Lifecycle Flow - Complete webhook-to-streaming flow

• Data Types - All enums and constants

• Webhooks - Event subscription details

• Environment Variables - credential modes and runtime knobs

• Quickstart Notes - Secondary quickstart guide

• Integrated Index - see the section below in this file

Having issues?

• Connection fails -> Common Issues

• Duplicate connections -> Webhook Gotchas

• No audio/video -> Media Configuration

• Start with preflight checks -> 5-Minute Runbook

Supported Products

Product Webhook Event Payload ID App Type

Meetings meeting.rtms_started / meeting.rtms_stopped

meeting_uuid

General App

Webinars webinar.rtms_started / webinar.rtms_stopped

meeting_uuid (same!) General App

Video SDK session.rtms_started / session.rtms_stopped

session_id

Video SDK App

Zoom Contact Center Voice Product-specific RTMS/ZCC Voice events Product-specific stream/session identifiers Contact Center / approved RTMS integration

Once connected, the core signaling/media socket model is shared across products. Meetings, webinars, and Video SDK sessions use the familiar start/stop webhooks. Zoom Contact Center Voice adds its own RTMS/ZCC Voice event family and should be treated as the same transport model with product-specific event payloads.

RTMS Overview

RTMS is a data pipeline that gives your app access to live media from Zoom meetings, webinars, and Video SDK sessions without participant bots. Instead of having automated clients join meetings, use RTMS to collect media data directly from Zoom's infrastructure.

What RTMS Provides

Media Type Format Use Cases

Audio PCM (L16), G.711, G.722, Opus Transcription, voice analysis, recording

Video H.264, JPG, PNG Recording, AI vision, thumbnails, active participant selection

Screen Share H.264, JPG, PNG Content capture, slide extraction

Transcript JSON text Meeting notes, search, compliance

Chat JSON text Archive, sentiment analysis

March 2026 Protocol Changes

• Zoom Contact Center Voice support: RTMS now covers Contact Center Voice audio and transcript scenarios.

• Transcript Language Identification control: transcript media handshakes now support src_language and enable_lid . Default behavior is LID enabled. Set enable_lid: false to force a fixed language.

• Single individual video stream subscription: RTMS can now stream one participant's camera feed at a time when data_opt is set to VIDEO_SINGLE_INDIVIDUAL_STREAM .

• Graceful client-initiated shutdown: backends can send STREAM_CLOSE_REQ over the signaling socket and wait for STREAM_CLOSE_RESP .

• Media keep-alive tolerance increased: media socket keep-alive timeout is now 65 seconds, not 35.

Two Approaches

Approach Best For Complexity

SDK (@zoom/rtms ) Most use cases Low - handles WebSocket complexity

Manual WebSocket Custom protocols, other languages High - full protocol implementation

Prerequisites

• Node.js 20.3.0+ (24 LTS recommended) for JavaScript SDK

• Python 3.10+ for Python SDK

• Zoom General App (for meetings/webinars) or Video SDK App (for Video SDK) with RTMS feature enabled

• Webhook endpoint for RTMS events

• Server to receive WebSocket streams

Need RTMS access? Post in Zoom Developer Forum requesting RTMS access with your use case.

Quick Start (SDK - Recommended)

import rtms from "@zoom/rtms";

// All RTMS start/stop events across products const RTMS_EVENTS = ["meeting.rtms_started", "webinar.rtms_started", "session.rtms_started"];

// Handle webhook events rtms.onWebhookEvent(({ event, payload }) => { if (!RTMS_EVENTS.includes(event)) return;

const client = new rtms.Client();

client.onAudioData((data, timestamp, metadata) => { console.log(Audio from ${metadata.userName}: ${data.length} bytes); });

client.onTranscriptData((data, timestamp, metadata) => { const text = data.toString('utf8'); console.log(${metadata.userName}: ${text}); });

client.onJoinConfirm((reason) => { console.log(Joined session: ${reason}); });

// SDK handles all WebSocket connections automatically // Accepts both meeting_uuid and session_id transparently client.join(payload); });

Quick Start (Manual WebSocket)

For full control or non-SDK languages, implement the two-phase WebSocket protocol:

const WebSocket = require('ws'); const crypto = require('crypto');

const RTMS_EVENTS = ['meeting.rtms_started', 'webinar.rtms_started', 'session.rtms_started'];

// 1. Generate signature // For meetings/webinars: uses meeting_uuid. For Video SDK: uses session_id. function generateSignature(clientId, idValue, streamId, clientSecret) { const message = ${clientId},${idValue},${streamId}; return crypto.createHmac('sha256', clientSecret).update(message).digest('hex'); }

// 2. Handle webhook app.post('/webhook', (req, res) => { res.status(200).send(); // CRITICAL: Respond immediately!

const { event, payload } = req.body; if (RTMS_EVENTS.includes(event)) { connectToRTMS(payload); } });

// 3. Connect to signaling WebSocket function connectToRTMS(payload) { const { server_urls, rtms_stream_id } = payload; // meeting_uuid for meetings/webinars, session_id for Video SDK const idValue = payload.meeting_uuid || payload.session_id; const signature = generateSignature(CLIENT_ID, idValue, rtms_stream_id, CLIENT_SECRET);

const signalingWs = new WebSocket(server_urls);

signalingWs.on('open', () => { signalingWs.send(JSON.stringify({ msg_type: 1, // Handshake request protocol_version: 1, meeting_uuid: idValue, rtms_stream_id, signature, media_type: 9 // AUDIO(1) | TRANSCRIPT(8) })); });

// ... handle responses, connect to media WebSocket }

See: Manual WebSocket Guide for complete implementation.

Media Type Bitmask

Combine types with bitwise OR:

Type Value Description

Audio 1 PCM audio samples

Video 2 H.264/JPG video frames

Screen Share 4 Separate from video!

Transcript 8 Real-time speech-to-text

Chat 16 In-meeting chat messages

All 32 All media types

Example: Audio + Transcript = 1 | 8 = 9

Critical Gotchas

Issue Solution

Only 1 connection allowed New connections kick out existing ones. Track active sessions!

Respond 200 immediately If webhook delays, Zoom retries creating duplicate connections

Heartbeat mandatory Respond to msg_type 12 with msg_type 13, or connection dies

Reconnection is YOUR job RTMS doesn't auto-reconnect. Media keep-alive tolerance is now about 65s; signaling remains around 60s

Transcript language drift Use src_language plus enable_lid: false when you want fixed-language transcription instead of automatic language switching

Single participant video only VIDEO_SINGLE_INDIVIDUAL_STREAM supports one participant at a time. A new VIDEO_SUBSCRIPTION_REQ overrides the previous selection

Graceful close is explicit now Use STREAM_CLOSE_REQ / STREAM_CLOSE_RESP when your backend wants to terminate the stream cleanly

Environment Variables

SDK Environment Variables

Required - Authentication

ZM_RTMS_CLIENT=your_client_id # Zoom OAuth Client ID ZM_RTMS_SECRET=your_client_secret # Zoom OAuth Client Secret

Optional - Webhook server

ZM_RTMS_PORT=8080 # Default: 8080 ZM_RTMS_PATH=/webhook # Default: /

Optional - Logging

ZM_RTMS_LOG_LEVEL=info # error, warn, info, debug, trace ZM_RTMS_LOG_FORMAT=progressive # progressive or json ZM_RTMS_LOG_ENABLED=true

Manual Implementation Variables

ZOOM_CLIENT_ID=your_client_id ZOOM_CLIENT_SECRET=your_client_secret ZOOM_SECRET_TOKEN=your_webhook_token # For webhook validation

Zoom App Setup

For Meetings and Webinars (General App)

• Go to marketplace.zoom.us -> Develop -> Build App

• Choose General App -> User-Managed

• Features -> Access -> Enable Event Subscription

• Add Events -> Search "rtms" -> Select:

• meeting.rtms_started

• meeting.rtms_stopped

• webinar.rtms_started (if using webinars)

• webinar.rtms_stopped (if using webinars)

• Scopes -> Add Scopes -> Search "rtms" -> Add:

• meeting:read:meeting_audio

• meeting:read:meeting_video

• meeting:read:meeting_transcript

• meeting:read:meeting_chat

• webinar:read:webinar_audio (if using webinars)

• webinar:read:webinar_video (if using webinars)

• webinar:read:webinar_transcript (if using webinars)

• webinar:read:webinar_chat (if using webinars)

For Video SDK (Video SDK App)

• Go to marketplace.zoom.us -> Develop -> Build App

• Choose Video SDK App

• Use your SDK Key and SDK Secret (not OAuth Client ID/Secret)

• Add Events:

• session.rtms_started

• session.rtms_stopped

Sample Repositories

Official Samples

Repository Description

rtms-samples RTMSManager, boilerplates, AI samples

rtms-quickstart-js JavaScript SDK quickstart

rtms-quickstart-py Python SDK quickstart

rtms-sdk-cpp C++ SDK

zoom-rtms Main SDK repository

AI Integration Samples

Sample Description

rtms-meeting-assistant-starter-kit AI meeting assistant with summaries

arlo-meeting-assistant Production meeting assistant with DB

videosdk-rtms-transcribe-audio Whisper transcription

Complete Documentation

Concepts

• Connection Architecture - Two-phase WebSocket design

• Lifecycle Flow - Webhook to streaming flow

Examples

• SDK Quickstart - Using @zoom/rtms SDK

• Manual WebSocket - Raw protocol implementation

• RTMS Bot - Complete bot implementation guide

• AI Integration - Transcription and analysis patterns

References

• Media Types - Audio, video, transcript, chat, screen share

• Data Types - All enums and constants

• Connection - WebSocket protocol details

• Webhooks - Event subscription

Troubleshooting

• Common Issues - FAQ and solutions

Resources

• Official docs: https://developers.zoom.us/docs/rtms/

• Data types: https://developers.zoom.us/docs/rtms/data-types/

• Media params: https://developers.zoom.us/docs/rtms/media-parameter-definition/

• Developer forum: https://devforum.zoom.us/

Need help? Start with Integrated Index section below for complete navigation.

Integrated Index

This section was migrated from SKILL.md .

RTMS provides real-time access to live audio, video, transcript, chat, and screen share from Zoom meetings, webinars, and Video SDK sessions.

Critical Positioning

Treat RTMS as a backend service for receiving and processing media streams.

• Backend role: ingest audio/video/share/chat/transcript, run AI/analytics, persist/forward data.

• Optional frontend role: Zoom App SDK or web dashboard that consumes processed stream data from backend transport (WebSocket/SSE/other).

• Kickoff model: backend waits for RTMS start webhook events, then starts stream processing.

Do not model RTMS as a frontend-only SDK.

Quick Start Path

If you're new to RTMS, follow this order:

Run preflight checks first -> RUNBOOK.md

Understand the architecture -> concepts/connection-architecture.md

• Two-phase WebSocket: Signaling + Media

• Why RTMS doesn't use bots

Choose your approach -> SDK or Manual

• SDK (recommended): examples/sdk-quickstart.md

• Manual WebSocket: examples/manual-websocket.md

Understand the lifecycle -> concepts/lifecycle-flow.md

• Webhook -> Signaling -> Media -> Streaming

Configure media types -> references/media-types.md

• Audio, video, transcript, chat, screen share

Troubleshoot issues -> troubleshooting/common-issues.md

• Connection problems, duplicate webhooks, missing data

Documentation Structure

rtms/ ├── SKILL.md # Main skill overview ├── SKILL.md # This file - navigation guide │ ├── concepts/ # Core architectural patterns │ ├── connection-architecture.md # Two-phase WebSocket design │ └── lifecycle-flow.md # Webhook to streaming flow │ ├── examples/ # Complete working code │ ├── sdk-quickstart.md # Using @zoom/rtms SDK │ ├── manual-websocket.md # Raw protocol implementation │ ├── rtms-bot.md # Complete RTMS bot implementation │ └── ai-integration.md # Transcription and analysis │ ├── references/ # Reference documentation │ ├── media-types.md # Audio, video, transcript, chat, share │ ├── data-types.md # All enums and constants │ ├── connection.md # WebSocket protocol details │ └── webhooks.md # Event subscription │ └── troubleshooting/ # Problem solving guides └── common-issues.md # FAQ and solutions

By Use Case

I want to get meeting transcripts

• SDK Quickstart - Fastest approach

• Media Types - Transcript configuration

• AI Integration - Whisper, Deepgram, AssemblyAI

I want to record meetings

• Media Types - Audio + Video configuration

• SDK Quickstart - Receiving media

• AI Integration - Gap-filled recording

I want to build an AI meeting assistant

• AI Integration - Complete patterns

• SDK Quickstart - Media ingestion

• Lifecycle Flow - Event handling

I want to build a complete RTMS bot

• RTMS Bot - Complete implementation guide

• Lifecycle Flow - Webhook to streaming flow

• Connection Architecture - Two-phase design

I need full protocol control

• Manual WebSocket - START HERE

• Connection Architecture - Two-phase design

• Data Types - All message types and enums

• Connection - Protocol details

I'm getting connection errors

• Common Issues - Diagnostic checklist

• Connection Architecture - Verify flow

• Webhooks - Validation and timing

I want to understand the architecture

• Connection Architecture - Two-phase WebSocket

• Lifecycle Flow - Complete flow diagram

• Data Types - Protocol constants

By Product

I'm building for Zoom Meetings

• Standard RTMS setup. Webhook event: meeting.rtms_started . Uses General App with OAuth.

• Start with SDK Quickstart or Manual WebSocket.

I'm building for Zoom Webinars

• Same as meetings, but webhook event is webinar.rtms_started . Payload still uses meeting_uuid (NOT webinar_uuid ).

• Add webinar scopes and event subscriptions. See Webhooks.

• Only panelist streams are confirmed available. Attendee streams may not be individual.

I'm building for Zoom Video SDK

• Webhook event: session.rtms_started . Payload uses session_id (NOT meeting_uuid ).

• Requires a Video SDK App with SDK Key/Secret (not OAuth Client ID/Secret).

• Once connected, the protocol is identical to meetings.

• See Webhooks for payload details.

Key Documents

1. Connection Architecture (CRITICAL)

concepts/connection-architecture.md

RTMS uses two separate WebSocket connections:

• Signaling WebSocket: Authentication, control, heartbeats

• Media WebSocket: Actual audio/video/transcript data

2. SDK vs Manual (DECISION POINT)

examples/sdk-quickstart.md vs examples/manual-websocket.md

SDK Manual

Handles WebSocket complexity Full protocol control

Automatic reconnection DIY reconnection

Less code More code

Best for most use cases Best for custom requirements

3. Critical Gotchas (MOST COMMON ISSUES)

troubleshooting/common-issues.md

• Respond 200 immediately - Delayed webhook responses cause duplicates

• Only 1 connection per stream - New connections kick out existing

• Heartbeat required - Must respond to keep-alive or connection dies

• Track active sessions - Prevent duplicate join attempts

Key Learnings

Critical Discoveries:

Two-Phase WebSocket Design

• Signaling: Control plane (handshake, heartbeat, start/stop)

• Media: Data plane (audio, video, transcript, chat, share)

• See: Connection Architecture

Webhook Response Timing

• MUST respond 200 BEFORE any processing

• Delayed response -> Zoom retries -> duplicate connections

• See: Common Issues

Heartbeat is Mandatory

• Signaling: Receive msg_type 12, respond with msg_type 13

• Media: Same pattern

• Failure to respond = connection closed

• See: Connection

Signature Generation

• Format: HMAC-SHA256(clientSecret, "clientId,meetingUuid,streamId")

• For Video SDK, use session_id in place of meetingUuid

• Webinars still use meeting_uuid (not webinar_uuid )

• Required for both signaling and media handshakes

• See: Manual WebSocket

Media Types are Bitmasks

• Audio=1, Video=2, Share=4, Transcript=8, Chat=16, All=32

• Combine with OR: Audio+Transcript = 1|8 = 9

• See: Media Types

Screen Share is SEPARATE from Video

• Different msg_type (16 vs 15)

• Different media flag (4 vs 2)

• Must subscribe separately

• See: Media Types

Quick Reference

"Connection fails"

-> Common Issues

"Duplicate connections"

-> Webhook timing

"No audio/video data"

-> Media Types - Check configuration

"How do I implement manually?"

-> Manual WebSocket

"What message types exist?"

-> Data Types

"How do I integrate AI?"

-> AI Integration

Document Version

Based on Zoom RTMS SDK v1.x and official documentation as of 2026.

Happy coding!

Remember: Start with SDK Quickstart for the fastest path, or Manual WebSocket if you need full control.