Replay a Workflow Recording
SkillDatabases & dataLets your agent replay a recorded HDF5 robot episode inside Isaac Sim to visually check what happened.
Available today. Use it from your connected AI after setup.
No other account needed.
Connect ahel once, and every AI you use reads what you have installed.
Then ask your AI: use the Replay a Workflow Recording skill
About this capability
Replay a recorded HDF5 episode inside Isaac Sim for visual verification. Use when the user asks to replay, play back, or step through an HDF5 recording.
What this skill tells your AI
The instructions your AI receives, as published by nvidia/skills in skills/i4h-workflow-dataset-replay/SKILL.md and read by ahel’s review.
Purpose
Replay the exact recorded action sequence through the matching workflow and inspect it visibly.
Instructions
- Run the checkout resolver and select the exact HDF5.
- Read the original workflow and requested episode.
- Inspect action-contract compatibility.
- Run the replay visibly in the foreground through completion.
Resolve the recording
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 "$ROOT"
find runs -name '*.hdf5' -type f -printf '%T@ %p\n' | sort -nr | head
Treat the resolver above as part of the skill contract: a hosted copy may run outside the base repository, so never assume the current checkout contains workflows/i4h_workflows. I4H_WORKFLOWS_REPO_URL selects the clone source. When I4H_WORKFLOWS is unset, derive the fallback directory from that URL; set I4H_WORKFLOWS only to reuse or choose a specific destination. Never replace an existing checkout.
Use an explicit or current-chain recording first. Otherwise select the newest plausible HDF5 and state that choice. Never substitute an older file after a failed recording.
Interpret natural ordinals as zero-based indices: first is 0, second is 1.
Inspect before launch
HDF5_PATH=/absolute/path/to/recording.hdf5
uv run --project tools/dataset i4h-dataset inspect "$HDF5_PATH" --segments
Resolve the original workflow from recording metadata and conversation context. Confirm the requested episode exists and its action width matches the workflow's replay Scene contract.
Replay
./run.sh <workflow> --replay "$HDF5_PATH" --episode <zero-based-index>
Keep the visible simulator and command in the foreground. Poll yielded execution until run.sh exits; do not detach or return while replay is still running.
Verify
Observe the complete trajectory, relevant objects, camera views, segment boundaries, and final status. If motion diverges, report the first mismatching segment or action-contract error. Do not change workflow, episode, or recording silently.
Troubleshooting
On launch failure, verify workflow metadata, episode existence, and action width. On divergence, report the first mismatching segment.
Prerequisites
Require the original workflow assets and a readable episode whose action width matches replay mode.
Limitations
Replay verifies stored actions in one Scene; it does not evaluate a learned policy or guarantee transfer to another Scene.
Examples
Replay the second episode.→ select the current recording, map “second” to index1, and observe the visible replay.
Completion gate
Report workflow, HDF5 path, episode index, frame/segment count, action width, exit/final status, and visible agreement or first mismatch.
Signals
- GitHub stars
- 3k
- Forks
- 387
- Last commit
- Sep 2026
Advanced
- Catalog kind
- skill
- Gateway key
i4h-workflow-dataset-replay- Source
- github.com/nvidia/skills