Live Sessions

Steel sessions can be viewed live directly from your app or dashboard.
With the new headful experience, live views now stream real-time video using WebRTC — low-latency, high-fidelity, and OS-accurate.

Legacy headless sessions continue to use the same debug URL but display content using Chrome’s screencasting for backward compatibility.

Embed Headful Live Sessions (Recommended)

What Changed

Steel’s live view now uses WebRTC-based video streaming at 25 fps (H.264), replacing Chrome’s screencasting and screenshot-based method.

Real-time OS-level capture
Stable 25 fps playback
Low-latency streaming with full visual fidelity

Tip: Headful sessions are now default for all new sessions.
You’ll use the same debugUrl, and Steel automatically chooses the proper playback technology.

Getting the Debug URL

When creating a session with the API, the response includes a debugUrl.
You can open this URL directly in your browser or embed it inside an application.

1import { Steel } from "steel-sdk";
2
3const client = new Steel({ apiKey: process.env.STEEL_API_KEY });
4const session = await client.sessions.create();
5
6console.log("Debug URL:", session.debugUrl);

Embedding in Your Application

Embed the session directly in your UI using an iframe:

<iframe
  src="{session.debugUrl}?interactive=true"
  style="width: 100%; height: 600px; border: none;"
></iframe>

Streams real-time browser output using WebRTC + H.264
Works in all major browsers with baseline H.264 support
interactive=true allows remote mouse/keyboard input for collaborative debugging or human-in-the-loop workflows

Note: For security reasons, debug URLs are unauthenticated.
Anyone with the debug URL can view or interact with that session.
Use your own-access controls if embedding in a user-facing product.

Supported Parameters (Headful)

Parameter	Type	Default	Description
`interactive`	boolean	`true`	Enables or disables remote control of the live session.

Example:

<iframe
  src={`${session.debugUrl}?interactive=false`}
  style="width: 100%; height: 600px; border: none;"
></iframe>

Disabling interactivity makes the view read-only, ideal for watch-only monitoring scenarios.

Headless (Legacy)

Headless live sessions remain supported for existing workflows.
They use Chrome’s screencasting instead of WebRTC and expose additional configuration options.

Configuration Options (Headless Only)

Parameter	Type	Default	Description
`theme`	string	`"dark"`	UI theme (`dark` or `light`)
`interactive`	boolean	`true`	Enable or disable interaction
`showControls`	boolean	`true`	Show or hide navigation UI
`pageId`	string	(empty)	Focus the view on a specific page/tab
`pageIndex`	string	(empty)	Display a specific tab by index

Example:

<iframe
  src={`${session.debugUrl}?theme=light&interactive=true&showControls=true&pageIndex=0`}
  style="width: 100%; height: 600px; border: none;"
></iframe>

Common Use Cases

Read-only viewer

<iframe
  src={`${session.debugUrl}?interactive=false`}
  style="width: 100%; height: 600px; border: none;"
></iframe>

Human-in-the-loop control

Allow humans to take over automation tasks or debug live workflows interactively using interactive=true.

Troubleshooting

If the embedded view appears blank or unresponsive:

Ensure the session is active (default timeout: 5 min).
Confirm your browser supports H.264 baseline playback.
Check your container has fixed dimensions (width and height).
Verify the correct session and valid API key were used.

Summary

All new sessions now run headful by default, streaming real-time video with WebRTC.
Use the same debugUrl to embed or view — Steel automatically determines the correct playback mode.

Headless live streams remain available for legacy sessions but will be phased out over time.