SKILL.md
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- 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_languageandenable_lid. Default behavior is LID enabled. Setenable_lid: falseto force a fixed language.
- Single individual video stream subscription: RTMS can now stream one participant's camera feed at a time when
data_optis set toVIDEO_SINGLE_INDIVIDUAL_STREAM.
- Graceful client-initiated shutdown: backends can send
STREAM_CLOSE_REQover the signaling socket and wait forSTREAM_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
RTMSManager, boilerplates, AI samples
JavaScript SDK quickstart
Python SDK quickstart
C++ SDK
Main SDK repository
AI Integration Samples
Sample
Description
rtms-meeting-assistant-starter-kit
AI meeting assistant with summaries
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/
- 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 usesmeeting_uuid(NOTwebinar_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 usessession_id(NOTmeeting_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)
-
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_idin place ofmeetingUuid
- Webinars still use
meeting_uuid(notwebinar_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"
"Duplicate connections"
"No audio/video data"
-> Media Types - Check configuration
"How do I implement manually?"
"What message types exist?"
-> Data Types
"How do I integrate AI?"
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.