**Overall Verdict:** Accept — the task is coherent and evaluable, with usable ALMA inputs and reference outputs; only a non-blocking archive naming/content-type mismatch and bounded review of very large files remain.

**Completeness Check:**
- Instruction: Complete — clear astrochemistry objective, CASA/Python workflow, required artifacts, and offline-use restriction.
- Inputs: Complete — all listed files are present and support the stated roles; the measurement-set payload is a readable POSIX tar stream despite its `.tar.gz` name and gzip declaration.
- Toolchain: Complete — CASA and Python are legally obtainable, with CASA and pipeline versions identified in the evidence; no credentials or network access are required.
- Reference output: Complete — the command/version text is readable, and the 3000×1200 PNG visibly contains the two requested panels, titles, inverted RA axis, arcsecond labels, 100 AU scale bar, and panel beams.
- Rubric: Complete — output format, layout, labeling, beam, scale-bar, title, and command-record requirements are specific enough for objective evaluation.

**File and Task Reachability:** Attachment set: `partially_reachable` for review purposes. I fully inspected `pds66_qa2_report.pdf`, `pds66_info.txt`, `pds66_output.txt`, and `pds66_image.png`; I inspected FITS header and tail ranges from `pds66_12co.fits`, and leading/trailing ranges from `pds66_cont.ms.tar.gz`. The FITS header is valid 32-bit floating-point data with 1024×1024×300 dimensions and CO spectral metadata. The archive prefix contains safe relative measurement-set paths and the sampled tail ends in tar padding; its middle and FITS data body were not downloaded because of their multi-gigabyte size. CASA/Python execution was not available in the review environment, so execution itself was not rerun. Task classification: `reachable`: a suitable single Linux workstation can extract the measurement set, run the documented `tclean`, export FITS, load the CO cube and continuum image in Python, and produce the required PNG and text record for objective evaluation. License keys, accounts, tokens, and other credentials are not required from the contributor. Confidential, proprietary, or internal material may be evaluated as submitted evidence without requiring additional disclosure.

**Special Screening:**
None — no affirmative evidence supports `ai_synthetic`, `public_benchmark`, or `synthetic_defect_fixture`. Public provenance was not independently checked because approved search was unavailable.

**Recommended Changes:**
The submission provides coherent ALMA documentation, a reproducible CASA command record, and a reference figure matching the requested visual contract. No material changes are required. A non-blocking polish improvement would be to align the measurement-set archive’s filename/content type with its actual tar encoding or document the appropriate extraction form.