setup-workshop-nemoclaw (in-sandbox side)

Sets up the NVIDIA Build an Agent workshop as an accessible JupyterLab instance inside an OpenShell/NemoClaw sandbox, then hands the user the port-forward + SSH commands and the token URL to open it in their browser.

This is one half of a two-skill pair:

Which side am I on?

Run the checks before doing anything. Inside the sandbox (use this skill): whoami → sandbox, /sandbox/ exists, docker/sudo are not found, and egress 403s come from the OpenShell proxy. On the host (use the operator skill instead): docker ps shows an openshell-<sandbox>-… container and the openshell CLI is on PATH.

When to use this skill

• User wants to run / access / go through the Build an Agent workshop from this sandbox. In the NemoClaw community repo this skill (plus its operator half) is the workshop setup pathway. The workshop content is not part of the community example: setup.sh clones it from the upstream workshop repo to /sandbox/workshop-build-an-agent, branch edwli-dev — stay on it.
• Do NOT use the setup-workshop skill that ships inside the cloned workshop repo — it is a bare-metal installer (nvwb + Docker + CUDA + sudo) for a GPU host. It fails in the sandbox by design, not by bug.

Operator prerequisites (the handoff contract)

One thing must be true before setup can succeed, and only the operator (outside the sandbox) can make it true. Verify with scripts/preflight.sh; if missing, send the operator the exact ask from references/operator-contract.md and stop until they confirm:

1. Egress policy allows: GET pypi.org + files.pythonhosted.org (installs); the NIM chat/embeddings routes on integrate.api.nvidia.com; POST /v1/retrieval/** on ai.api.nvidia.com (modules 2/3 reranker — NOT covered by the legacy /v1/ranking rule); POST /search on api.tavily.com (modules 1/2/5 web search); all methods on api.smith.langchain.com (module 3 + workshop-wide tracing); GET /encodings/** on openaipublic.blob.core.windows.net (module-7 tiktoken); GET registry.npmjs.org for the node binary (module-5 "Deep Agents Client" tile — without it demo/ can't npm install and the tile only ever serves its setup page); GET/POST/DELETE on mcp.tavily.com for node (module-2 PART 2A remote MCP — the shipped default); and git smart-HTTP on github.com scoped to the workshop repo — setup.sh clones the workshop content from upstream, so this is a standard prerequisite here (skip only if a clone already exists). preflight.sh probes all of these and prints the exact ask for each gap. Not a prerequisite: NVIDIA_API_KEY. It is EXPECTED to be absent — the learner sets it in the workshop's Secrets Manager tile after launch, and preflight only WARNs about it. Leaving it unset is what makes that work: start-jupyter.sh sources secrets.env into the server env at launch and kernels inherit it, but load_dotenv() never overrides an already-set variable — so a key staged before launch would shadow every later Secrets Manager edit until a restart. Never accept a key through chat; if the operator does want one pre-seeded, they write it from the host with stage-nvidia-key.sh (a real nvapi-… key only — never COMPATIBLE_API_KEY, which is the agent's own sk-… proxy credential and yields a confusing 401).

Optional third item — /dev/pts read-write in filesystem_policy — is needed only for the launcher's Terminal tile (terminado → pty.fork). Setup does NOT block on it: start-jupyter.sh probes os.openpty() and launches with terminals disabled when denied. The grant only takes effect at a sandbox recreate (the supervisor parses filesystem policy at container boot; a live policy apply won't activate it, even for new processes) — after a recreate that includes it, setup enables terminals automatically.

There is no operator knob for the netlink/seccomp block — it is compiled into the in-container OpenShell supervisor (Rust seccompiler), not the Docker profile. You fix it inside the sandbox with the LD_PRELOAD shim below; this was operator-pre-approved as the sanctioned fallback. Never dodge seccomp via docker exec — that also escapes Landlock egress enforcement. FORBIDDEN.

Fast path (idempotent scripts)

SKILL_DIR is wherever this skill lives — resolve it, don't assume. Known locations: the agent skill library (/sandbox/.hermes-data/skills/**/setup-workshop-nemoclaw, where the operator stages it from the community example) or, after the clone, the repo checkout (/sandbox/workshop-build-an-agent/.claude/skills/setup-workshop-nemoclaw).

SKILL_DIR=$(dirname "$(find /sandbox -maxdepth 6 -path '*/setup-workshop-nemoclaw/SKILL.md' 2>/dev/null | head -1)")
bash "$SKILL_DIR/scripts/preflight.sh"      # verifies the operator contract + environment; prints exact asks if not met
bash "$SKILL_DIR/scripts/setup.sh"          # clone (if missing), venv+deps, shim, bridge, launcher, %pip neutralize
bash "$SKILL_DIR/scripts/start-jupyter.sh"  # ONE server on 127.0.0.1:8888, prints + saves token URL
cat /sandbox/workshop-url.txt               # http://127.0.0.1:8888/lab?token=...

All three scripts are idempotent and verify before acting. If a step fails, read the matching section of references/sandbox-internals.md for the root cause and manual commands.

What the scripts do (and why) — the hard-won details

Do NOT skip or reorder these. Each fixes a specific sandbox failure discovered the hard way (full rationale + diagnostics in references/sandbox-internals.md).

1. TLS / CA bundle. uv and pip do not use the system trust store, and TLS terminates at the OpenShell L7 proxy. You MUST export SSL_CERT_FILE=/etc/openshell-tls/ca-bundle.pem (and PIP_CERT = same). ⚠️ /etc/ssl/certs/ca-certificates.crt is WRONG here — it lacks the proxy CA and breaks uv with invalid peer certificate: UnknownIssuer (--native-tls / --system-certs do not help).
2. venv + pinned CPU deps. uv venv $REPO/.venv; install the exact pinned set in templates/requirements-sandbox.txt. It includes the packages the repo's requirements.txt needs for the UI that early attempts missed: jupyter-app-launcher (zero tiles without it), voila, jupyterlab-git, streamlit + langgraph-sdk (client tiles), and ziglang (shim compiler). Never install torch/unsloth/cudf — they are GPU-only (module-4 training; module-7's optional cudf exercise, which falls back to CPU without them), this sandbox has no GPU, and installing them hangs voila.
3. Netlink LD_PRELOAD shim (templates/netlink-stub.c). The sandbox seccomp filter denies socket(AF_NETLINK,…) → EPERM, so getifaddrs() fails; ipykernel calls it at ZMQ bind regardless of transport (IPC does not avoid it), and an empty interface list trips a ZMQ assert (ip_resolver.cpp:543) → every kernel dies, voila hangs at "Running…". The shim stubs getifaddrs/if_nameindex to return a one-entry lo/127.0.0.1 list (non-empty is mandatory). Build with python -m ziglang cc (no system gcc; npm is 403-blocked). Preload it only on the Jupyter process tree, never session-wide.
4. Bridge labextension (assets/devx-jupyterapp-bridge/, checked-in source). The in-lesson buttons call openVoila() → window.parent.jupyterapp, which only AI Workbench's DevX layer normally injects. npm being 403-blocked, this is a hand-crafted federated labextension (Module Federation remoteEntry.js, ~2 KB) whose plugin sets window.jupyterapp = app. Copy the directory into $VENV/share/jupyter/labextensions/ — no archive, no build step.
5. Launcher config + anti-duplication (templates/jp_app_launcher.yaml, 11 tiles: 7 modules + Secrets Manager + Simple Agents/Deep Agents/NemoClaw clients). The workshop YAML hardcodes /project/... (a Workbench mount that doesn't exist here; symlinking /project fails — no root). The template rewrites paths to the repo; it goes in $REPO/.launcher-config/ with JUPYTER_APP_LAUNCHER_PATH pointing at it. The extension merges configs from both cwd AND that path, so ALSO move the repo-root jp_app_launcher.yaml aside (to /sandbox/original-root-jp_app_launcher.yaml.bak), delete any stale .ipynb_checkpoints/jp_app_launcher-checkpoint.yaml, and launch from cwd /sandbox — or you get 22 duplicate tiles (the extra set shows letter icons like 1A/2A/…). The Secrets Manager tile MUST be type: jupyterlab-commands invoking docmanager:open with factory: "Voila Preview" — the authenticated in-app path the per-module buttons use. type: notebook-voila deadlocks behind jupyter-server-proxy (HTTP 599); a raw type: url → /voila/render/... iframe carries no auth token → 302 → login → hangs at "Running…".

5b. Terminal rcfile (setup.sh 4b + start-jupyter.sh --ServerApp.terminado_settings). The Terminal tile otherwise spawns a LOGIN bash: /etc/profile resets PATH and the image's read-only /sandbox/.bashrc re-prepends only the hermes dirs — the workshop venv (sole home of langgraph/uvicorn/streamlit) drops off PATH and every lesson terminal command dies with "command not found". The rc files cannot be replaced (the supervisor denies creating .bashrc*/.profile* in /sandbox). Fix: generate $REPO/.launcher-config/terminal-bashrc (sources /sandbox/.bashrc for the proxy env, prepends the venv, exports SSL_CERT_FILE/PIP_CERT, set -a-sources variables.env + secrets.env for AI-Workbench parity — module-2's uvicorn mcp_server:app hard-requires TAVILY_API_KEY, and a terminal-launched langgraph dev needs LANGSMITH_TRACING for the observability lesson — and sets npm fail-fast vars) and launch terminals as NON-login bash --rcfile <that file>.

5c. aiohttp proxy trust (setup.sh 4c). All egress rides HTTP(S)_PROXY env vars; httpx/requests honor them, aiohttp needs trust_env=True. langchain-nvidia-ai-endpoints' ASYNC path uses aiohttp, so every langgraph-served agent run (ainvoke → ChatNVIDIA) died at Cannot connect to host integrate.api.nvidia.com:443 [Temporary failure in name resolution] while sync calls worked. Fix: a .pth-imported module in the venv site-packages (zz-workshop-aiohttp-trust-env.pth → _workshop_aiohttp_trust_env.py) defaults trust_env=True when proxy env is present. (sitecustomize.py is unusable — shadowed by /usr/local/lib/nemoclaw-patches on PYTHONPATH.)

6. Neutralize %pip cells (scripts/neutralize_pip_cells.py). Cell 1 of the 8 code/secrets_management/secrets_management_*.ipynb notebooks runs %pip install -r ../../requirements.txt (pulls torch etc. → hangs voila; the uv venv has no pip anyway). The script comments out only that line and preserves the load_dotenv calls. Idempotent.

6b. Lesson content sandbox notes (scripts/sandbox_content_notes.py). Marker-guarded SANDBOX NOTE admonitions + /project/ → $REPO rewrites inside bash fences, for lessons whose primary flow needs egress/hardware this sandbox deliberately lacks: module-2 mcp.md (remote MCP via npx — use the lesson's own PART 2B local server; verified working) and migrate.md (local NIM needs Docker+GPU), module-4 GPU lessons, module-5 experience_deep_agent.md (skip the python3.12 -m venv step — deps are pre-installed; npm/Docker unavailable by design), module-6 CLI setup pages (Docker/npm), plus cd /project/... path fixes in module-6 lessons.

7. Single-server discipline (scripts/start-jupyter.sh). Keep exactly one JupyterLab server on 8888. Stale servers steal the port bind — the relaunched (shim-carrying) server never takes over, tiles vanish, and the shim "mysteriously" stops working. Jupyter traps SIGTERM, so the script kill -9s stale jupyter-lab/voila/ipykernel, confirms the port is free, launches with the full env (SSL_CERT_FILE, JUPYTER_APP_LAUNCHER_PATH, venv-first PATH so spawned voila/ streamlit resolve, JUPYTER_RUNTIME_DIR=/tmp/jrt, LD_PRELOAD=<shim>) from cwd /sandbox with --ServerApp.root_dir=$REPO --ip 127.0.0.1 --port 8888 --no-browser --ServerApp.allow_remote_access=False, then verifies the running server's /proc/<pid>/environ actually contains LD_PRELOAD. It reuses the previous token when one exists so the user's saved URL stays valid across restarts. It also set -a-sources $REPO/variables.env + $REPO/secrets.env into the server env before launch (AI-Workbench parity for KERNELS): kernels/voila/tiles inherit the server env, which is how LANGSMITH_TRACING and other variables.env settings reach kernels at all. ⚠️ Sourcing secrets.env here is a double-edged sword, and the reason NVIDIA_API_KEY is deliberately left unset. load_dotenv() does not override an already-set variable, so any key present at launch SHADOWS later edits to the file — the learner fixes the key in the Secrets Manager, the file on disk is right, and kernels keep sending the stale value until a restart. Verified 2026-07-27: all 13 notebooks that reference NVIDIA_API_KEY call load_dotenv() first, and none read os.environ[...] without it — so an unset key costs nothing and keeps load_dotenv() authoritative. (An earlier version of this note claimed "several notebooks read os.environ directly with no load_dotenv"; that was wrong, and it was the justification for the injection that caused the stale-key bug.) Corollary: if a key IS pre-seeded from the host, RE-RUN this script (token/URL survive) so kernels pick it up.
8. Workshop skills → agent skill library (setup.sh, final step). The NemoClaw harness only scans its own library (/sandbox/.hermes-data/skills/) — repo-local .claude/skills are invisible to it, so without this step a resident agent asked about the workshop denies knowing any workshop skills even after a successful setup. In the community-example flow the operator stages this example's skill copies (modules 1–7, workshop, and this skill) into the library BEFORE setup; those staged copies are canonical and are never overwritten. This step only fills the gaps from the cloned repo (nvwb, nvwb-project, and any workshop skill the operator did not stage) — set FORCE_SKILL_REFRESH=1 to overwrite from the clone instead. Skills appear in hermes skills list as local/enabled immediately, and new agent sessions pick them up automatically; a session already in flight may need a fresh session to see them. Excluded on purpose: setup-workshop-nemoclaw-operator (host-side) and the workshop repo's setup-workshop (bare-metal GPU installer). ⚠️ THIS skill itself propagates from the RUNNING copy ($SKILL_DIR), never from the repo checkout — re-running setup.sh used to silently revert an operator-staged skill update to the repo's older version.

Report back to the user (the skill's real output)

The Jupyter token is masked by the gateway's secret redaction, so the URL is saved to /sandbox/workshop-url.txt — point the user there rather than pasting the token. Once start-jupyter.sh succeeds, send the user/operator:

JupyterLab is up (one server, 127.0.0.1:8888, kernels verified). To reach it: (1) on the sandbox host, run openshell forward service <sandbox> --target-port 8888 --local 8888 (foreground — leave it open); (2) from your laptop, ssh -N -L 8888:localhost:8888 <user>@<host> (Teleport: tsh ssh -N -L 8888:localhost:8888 <user>@<node-name> — node name from tsh ls; -N is SILENT when it works); (3) open the token URL from /sandbox/workshop-url.txt (readable on the host via docker exec <container> cat /sandbox/workshop-url.txt). FYI: keep step (1)'s command handy — the forward dies silently with the shell or agent session that spawned it (openshell forward list does not track it). If the URL ever stops responding, re-run that same command on the host to restore access.

Agent processes live in an inner network namespace — a server bound even to 0.0.0.0 is unreachable at the container IP. The gRPC forward + SSH hop is the only inbound path. Details live in the operator skill.

Verification

• $VENV/bin/jupyter lab list shows exactly one server on 127.0.0.1:8888, and tr '\0' '\n' < /proc/<server-pid>/environ | grep LD_PRELOAD shows the shim.
• curl -s -o /dev/null -w '%{http_code}' http://127.0.0.1:8888/lab → 302 (auth redirect = alive); with the token appended → 200.
• Tile check without a browser: curl -X POST http://127.0.0.1:8888/jupyterlab-app-launcher?token=… -d '{"method":"init_launcher"}' → 11 tiles. (GET on that route → 405; /jupyter_app_launcher/get_config → 404 — both expected.)
• Skill propagation: hermes skills list shows module-1…module-7, workshop, and setup-workshop-nemoclaw as local/enabled.
• Terminal tile (only when /dev/pts is granted): POST /api/terminals with the token → 200 (spawns a shell; DELETE /api/terminals/<name> to clean up).
• In the browser: 11 tiles, no duplicates; module lesson pages load; the Secrets Manager tile and in-lesson secrets buttons open Voila Previews (not a "Running…" hang); kernels start; a module-2 rerank call returns 200.

Pitfalls

• Terminal tile → "Launcher Error: Unhandled error" (500 on POST /api/terminals; log ends OSError: out of pty devices) → the real error is a swallowed EACCES from os.openpty(): Landlock lacks rw /dev/pts. Operator remedy: the operator skill's Phase 1b token-window-guarded container restart (the grant is applied with Phase 1, but fs policy is parsed at container boot — a live apply changes nothing, even for new processes). Details in references/sandbox-internals.md.
• Wrong CA bundle (ca-certificates.crt) → uv TLS failures. Use /etc/openshell-tls/ca-bundle.pem.
• Skipping the shim → kernels never start (Kernel died before replying to kernel_info); voila tiles hang at "Running…". Empty-list shims are NOT enough — the interface list must contain lo.
• A leftover /sandbox/.jupyter/jupyter_server_config.py forcing transport = "ipc" (an abandoned experiment) — remove it; IPC alone never fixes kernels and just adds moving parts. setup.sh cleans it up.
• Not moving the root launcher YAML / launching from the repo root → 22 duplicate tiles.
• Any type: url tile without args: {} → frontend crash (Cannot read properties of undefined (reading 'createNewWindow')).
• Installing torch/unsloth/cudf → hangs, wasted egress; GPU-only (mod-4 training; mod-7's cudf exercise).
• More than one Jupyter server on 8888 → tiles vanish / stale server without the shim answers. kill -9; SIGTERM is trapped.
• curl through /proxy/absolute/<port>/ appears to hang (chunked stream) and curl -I returns 405 — red herrings; test voila via /voila/render/... with the token, or in the browser.
• duckdb import segfaults in this sandbox — harmless, nothing in code/ uses it. joblib "serial mode" warning — benign.
• Trying docker exec to bypass seccomp → ALSO bypasses Landlock. FORBIDDEN.
• Switching off branch edwli-dev (e.g. nvwb switch-branch) → don't.
• Simple Agents Client renders but needs a separate LangGraph backend (a module exercise) to chat; Deep Agents Client intentionally serves a "setup required" page until its backend + npm-built client exist. Neither is a setup defect.
• Module-2 migrate.md (local NIM: Docker+GPU) is read-through-only here — same category as module-4 02/03 (GPU), module-5 Docker sandbox/client build, and module-6 CLI installers. sandbox_content_notes.py marks all of them in the lesson pages.
• Heavy notebooks (module-4 SDG generates 250 records) can rate-limit other concurrent LLM work on the same NVIDIA API key (429s) — run heavy modules sequentially.