Iso Review

ISO Review

Audit a dataset for ISO-standardisable fields and optionally refactor to the standard.

When to invoke

• User asks "is this using ISO standards?", "what could be standardised here?", "audit against ISO".
• Preparing a dataset for external distribution, where standards-compliance aids interoperability.

Standards covered

| Standard | Scope | Detection heuristics | |---|---|---| | ISO 3166-1 (countries) | alpha-2 (US), alpha-3 (USA), numeric (840) | Column names country, nation, country_code; values matching country names or 2/3-letter codes | | ISO 3166-2 (subdivisions) | e.g. US-CA, GB-ENG | State / province / region columns | | ISO 3166-3 (formerly-used) | Historical country codes | USSR, DDR, YUG values | | ISO 4217 (currencies) | USD, EUR, JPY | Currency columns, symbols in amounts | | ISO 639 (languages) | 639-1 (en), 639-2/3 (eng) | Language columns, free-text language labels | | ISO 8601 (dates/times) | YYYY-MM-DD, YYYY-MM-DDTHH:MM:SSZ, durations | Date-like columns in non-ISO formats | | ISO 80000 / SI units | SI units and prefixes | Unit columns, mixed unit systems | | ISO 3166-1 alpha-2 in emails / URLs (TLDs) | — | Domain / email columns with ccTLDs | | IANA time zones (not ISO but standard) | Europe/London | Timezone columns | | IANA media types / MIME | application/json | Content-type / format columns | | ISO 10962 (CFI) | Financial instrument classification | Instrument columns | | ISO 6166 (ISIN) | Securities identifiers | Security ID columns; checksum validation | | ISO 17442 (LEI) | Legal Entity Identifier | Entity ID columns; 20-char format |

Procedure

1. Profile the dataset — column names, types, samples, unique-value sets for low-cardinality columns.
2. Pattern-match to standards — use header heuristics (column-name keywords) plus value heuristics (regex, known-value sets from pycountry, iso4217, langcodes, etc.).
3. Classify each candidate column:

• Compliant — already matches the standard cleanly.
• Partially compliant — most values match; some don't (report exceptions).
• Non-compliant, easily refactorable — values can be deterministically mapped (e.g. "United States" → "US").
• Non-compliant, ambiguous — requires user input (e.g. short codes that could be 3166-1 or 3166-2, date formats 01/02/2024 that could be UK or US ordering).

1. Produce a review report iso_review.md:

• Per column: applicable standard, compliance status, evidence, recommended canonical form, refactor feasibility.
• Priority list — which columns to standardise first, based on impact + feasibility.

1. Offer refactor mode (require explicit user confirmation):

• For each "easily refactorable" column, apply the mapping and add the standardised column (or overwrite, per user choice).
• For dates, enforce ISO 8601 (with user-confirmed source-format assumption).
• For currencies, promote symbols / free-text names to ISO 4217 codes.
• Route through existing skills where they apply: standardise-country-names, add-iso3166, enrich-with-currency.

1. Validate — re-scan after refactor and report residual non-compliance.
2. Update the data dictionary — note the standard each column now follows.

Dependencies

pip install pandas pycountry langcodes iso4217 python-stdnum python-dateutil babel

Edge cases

• Mixed standards in one column — rare but real (e.g. a country column mixing alpha-2 and full names). Report and pick a target form with the user.
• Date format ambiguity (01/02/2024) — never guess. Require user confirmation; prefer source metadata or data dictionary for the answer.
• Historical values — ISO 3166-3 covers formerly-used codes; offer this rather than forcing a successor.
• Checksum-validated identifiers (ISIN, LEI) — verify the checksum; report invalid entries, do not silently accept.
• Non-ISO regional standards (e.g. FIPS codes) that look like ISO — note them, don't conflate.
• Performance — for very large datasets, sample for detection, then apply refactor in full-file pass.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: danielrosehill
• Source: danielrosehill/Claude-Data-Wrangler-plugin
• License: MIT

Install and usage instructions live in the source repository linked above.