First Viewer Review¶
This page starts after First Published Conversion is already complete.
It applies to both:
shared_accountafter Lab Machine Quick Start- a lab member using their own account after Personal Account Setup
The goal is simple:
- open the converted dataset locally in the browser viewer
- confirm that the newest episode actually renders
- recognize the most common local viewer failures quickly
Before You Start¶
Make sure these are already true:
- the current account already has the viewer toolchain prepared
- at least one episode was converted successfully
- the
Convertercard ended at: Latest dataset ready for review- the
Published Folderfield still points at the dataset you want to inspect
If those are not true yet, go back to:
- Viewer Setup
- Personal Account Setup if you are using your own account
- First Published Conversion
Normal workflow note:
- on
shared_account, local viewer setup should already be part of account provisioning - on a personal account, the viewer setup should already be covered by Personal Account Setup
1. Check The Viewer Target¶
Before clicking anything, confirm the operator console still points at the right published dataset:
Published Folder- should be the dataset you just converted into
The viewer path uses that target to resolve the local dataset to open.
Important:
Open Vieweropens the latest episode in that dataset- for a first smoke test, that is usually exactly what you want
2. Open The Viewer¶
In the operator console, use:
Open Viewer
on the Converter card.
What should happen:
- the backend checks that the published dataset exists
- it ensures the local dataset server is running
- it starts the local viewer server if needed
- it opens the resolved local episode URL for the latest episode in that dataset
The supported workflow is local-only:
- the viewer server runs on this machine
- the browser also runs on this machine
- the viewer URL uses this account's local viewer port
You do not need to manually start the viewer server in the normal workflow. You also do not need to manually expose the dataset to the viewer.
3. What Success Looks Like¶
The artifacts section should now show:
Dataset- the published folder name
Viewer- the resolved local viewer URL
A successful first viewer review means:
- the browser opens the local dataset page
- the newest episode loads
- RGB streams render
- depth preview streams render if depth was published
- the episode-level charts and metadata load without obvious missing-data errors
4. If Open Viewer Fails Immediately¶
Typical causes are:
- the viewer repo is missing
- expected at:
../lerobot-dataset-visualizer
bunis missing- expected at:
~/.bun/bin/bun
- the production viewer bundle was never built
- the published dataset target does not exist on disk
In that case, go back to:
and rerun:
5. If The Viewer Server Starts But The Page Still Looks Wrong¶
Known local issues we have already seen:
- missing production build marker:
.next/BUILD_ID- proxy environment variables interfering with local dataset requests
- wrong or stale published dataset target in the operator console
The normal Open Viewer path already handles the local proxy/runtime setup, so
the first response should be:
- stop trying manual browser-side workarounds
- rerun the viewer setup script
- try
Open Vieweragain
If you still need a manual check, verify the local dataset metadata exists:
cd ~/spark-workspace/spark-data-collection
ls published/<dataset_id>/meta/info.json
ls published/<dataset_id>/meta/spark_conversion
6. Optional Manual Fallback¶
Only if Open Viewer is still failing and you need to isolate whether the
problem is in the dataset or the console integration, you can start the viewer
manually from the sibling repo.
Important:
- this only makes sense after at least one
Open Viewerattempt - the console path is what starts both local services for the selected dataset
- replace
<viewer_base_url>with the URL shown in the operator console if you are not using the default account-local port - replace
<dataset_base_url>with the local dataset-server base URL if you overrode it
Manual start:
cd ~/spark-workspace/lerobot-dataset-visualizer
env -u http_proxy -u https_proxy -u HTTP_PROXY -u HTTPS_PROXY -u ALL_PROXY -u all_proxy -u NO_PROXY -u no_proxy \
DATASET_URL=<dataset_base_url>/datasets \
PORT=<viewer_port> \
~/.bun/bin/bun start
That is only for debugging. The normal workflow should stay:
Open Viewer
What Success Looks Like¶
Your first viewer review is successful when:
Open Vieweropens a local dataset URL- the newest episode page loads
- RGB streams render
- depth preview renders when depth exists
- the dataset shown in the browser matches the dataset in the operator console
At that point, the basic end-to-end local workflow is working:
- raw recording
- published conversion
- browser inspection