Convert Workflow HDF5 to LeRobot

SkillDatabases & data

Lets your agent convert HDF5 recordings of agent tasks into LeRobot datasets with parquet files, metadata, and videos.

Available today. Use it from your connected AI after setup.

Connect ahel once, and every AI you use reads what you have installed.

Then ask your AI: use the Convert Workflow HDF5 to LeRobot skill

About this capability

Convert an agentic HDF5 recording into a LeRobot dataset (parquet, meta, videos). Use when asked to convert HDF5, prepare for training, or export to LeRobot; not for viewing — use [[i4h-lerobot-viz]].

What this skill tells your AI

The instructions your AI receives, as published by nvidia/skills in skills/i4h-workflow-dataset-convert/SKILL.md and read by ahel’s review.

Purpose

Preserve recorded actions, state, cameras, task text, and embodiment labels in a local LeRobot dataset.

Instructions

  1. Run the checkout resolver and select the source HDF5.
  2. Read the workflow, Scene, embodiment, and instruction.
  3. Run conversion for the selected successful episodes.
  4. Inspect metadata, parquet, videos, and feature widths.

Resolve and inspect

export I4H_WORKFLOWS_REPO_URL="${I4H_WORKFLOWS_REPO_URL:-https://github.com/isaac-for-healthcare/i4h-workflows}"
I4H_REPO_DIR_NAME="${I4H_WORKFLOWS_REPO_URL%/}"
I4H_REPO_DIR_NAME="${I4H_REPO_DIR_NAME##*/}"
I4H_REPO_DIR_NAME="${I4H_REPO_DIR_NAME##*:}"
I4H_REPO_DIR_NAME="${I4H_REPO_DIR_NAME%.git}"
[ -n "$I4H_REPO_DIR_NAME" ] || { echo "Cannot derive a checkout name from I4H_WORKFLOWS_REPO_URL" >&2; exit 2; }
ROOT="${I4H_WORKFLOWS:-$(git rev-parse --show-toplevel 2>/dev/null)}"
if [ ! -d "$ROOT/workflows/i4h_workflows" ]; then
  ROOT="${I4H_WORKFLOWS:-$HOME/$I4H_REPO_DIR_NAME}"
  [ -d "$ROOT/workflows/i4h_workflows" ] || git clone "$I4H_WORKFLOWS_REPO_URL" "$ROOT"
fi
export I4H_WORKFLOWS="$ROOT"
cd "$ROOT"
HDF5_PATH=/absolute/path/to/recording.hdf5
uv run --project tools/dataset i4h-dataset inspect "$HDF5_PATH" --segments

Treat the resolver above as part of the skill contract: a hosted copy may run outside the base repository, so never assume the current checkout contains workflows/i4h_workflows. I4H_WORKFLOWS_REPO_URL selects the clone source. When I4H_WORKFLOWS is unset, derive the fallback directory from that URL; set I4H_WORKFLOWS only to reuse or choose a specific destination. Never replace an existing checkout.

Use the explicit/current-chain recording. Resolve its workflow and Scene from recording metadata/context, then read the Scene manifest for the embodiment and instruction. Use the embodiment manifest for labels. Do not assume state width equals action width; the converter derives both from the recording.

Convert

RUN_DIR="$(pwd)/runs/<workflow>/$(date +%Y%m%d_%H%M%S)"
DATASET_DIR="$RUN_DIR/lerobot/local/<name>"
mkdir -p "$(dirname "$DATASET_DIR")"
[ ! -e "$DATASET_DIR" ] || { echo "Destination already exists: $DATASET_DIR" >&2; exit 2; }
uv run --project tools/dataset i4h-dataset convert \
  "$HDF5_PATH" "$DATASET_DIR" \
  --robot <embodiment> \
  --repo-id "local/<name>" \
  --successful-only \
  --task "<instruction>"

Use --fps or --skip-frames only when the user requests it or source metadata justifies it. Keep the default H.264 video codec for compatibility with GR00T's fast decord loader; select another --video-codec only when the target consumer requires it.

Conversion writes aggregate meta/stats.json for downstream policy loaders. Native G1 rule-based WBC recordings already contain 43-D state and 50-D action; the converter recognizes that contract and writes GR00T's required semantic meta/modality.json automatically. For a G1 recording made through the legacy 23-D Pink/keyboard contract and destined for a 50-D G1 WBC policy Task, add --g1-wbc-policy-actions. That explicit mapping combines the measured 43-joint state with the recorded navigation, base-height, and torso commands; require source action width 23 and state width 43.

Verify

Require:

  • meta/info.json
  • meta/stats.json
  • meta/modality.json when the target trainer requires semantic modality slices
  • episode parquet data
  • video files for every recorded camera
  • converted episode count matching selected successful sources
  • action/state feature widths and names matching the recording plus embodiment descriptor

For G1, require modality metadata for both supported paths: native state=43/action=50, or explicitly mapped state=43/source-action=23/output-action=50. Treat a native 50-D dataset without meta/modality.json as incomplete.

Treat missing inputs or zero converted episodes as failure. If conversion leaves a partial destination, quarantine or remove that exact incomplete directory before retrying; never report it as usable.

Troubleshooting

On dimension errors, resolve the source workflow and embodiment again. On missing videos, confirm frames existed before conversion.

Prerequisites

Require a readable HDF5 recording and its matching Scene plus embodiment manifests.

Limitations

Conversion cannot reconstruct missing cameras, actions, state, task text, or successful episodes.

Examples

  • Convert my scissor pick-and-place recording into a LeRobot dataset. → resolve so101, convert successful episodes, and verify metadata, parquet, and both camera videos.

Completion gate

Report source HDF5/workflow, embodiment, task text, source/converted/skipped counts, action/state widths, output directory/repo id, aggregate-stats/modality/parquet/video checks, and any missing modality.

Signals

GitHub stars
3k
Forks
387
Last commit
Sep 2026
Advanced
Catalog kind
skill
Gateway key
i4h-workflow-dataset-convert
Source
github.com/nvidia/skills