Name: testland/dst-transition-reference
Rating: 75.2 (1 reviews)
Author: testland

testland/dst-transition-reference

Pure-reference catalog of Daylight Saving Time (DST) transition patterns and their canonical bug classes. Covers the spring-forward (skipped hour: 02:00 → 03:00 local) and fall-back (repeated hour: 02:00 → 01:00 local) transitions, the historical irregularity of DST (different jurisdictions, transitions on different dates, some regions abolish DST or never adopted it), the IANA timezone database (tz / Olson DB) as the canonical source, and the testable behaviors DST creates (duplicate / missing local timestamps, cron jobs that fire 0 or 2 times, billing periods that miss / double-count, recurring meetings on transition days). Per-jurisdiction DST-rule tables and refreshable per-region test-data fixtures live in references/. Use when designing or auditing time-handling code or test cases.

Quality

94%

Does it follow best practices?

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Securityby

Passed

No findings from the security scan

Quality

Content

85%

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

A well-structured reference skill with strong actionability, clear workflow, and clean one-level progressive disclosure to a real bundle file. The main drag on conciseness is inline time-sensitive 2026 dates that would sit better in the refreshable fixture file.

Suggestions

Move the inline 2026 fixture timestamps (e.g., 2026-03-08, 2026-11-01) into references/jurisdictions-and-fixtures.md and reference them generically from the body, since the skill itself flags these dates as refreshable and stale-prone.

Tighten the Overview and 'When to use' sections — they partially restate mechanics already covered under 'DST mechanics'.

Consider collapsing the worked example's per-library bullets into the existing library-behavior table to avoid restating pytz/zoneinfo/Java results twice.

Dimension	Reasoning	Score
Conciseness	Mostly information-dense (tables of library behavior, bug classes, anti-patterns) but carries time-sensitive 2026 fixture dates inline throughout rather than isolating them, and the Overview/'When to use' prose could be tightened.	2 / 3
Actionability	Gives concrete executable guidance: exact test timestamps ('2026-03-08 02:30 America/New_York'), library-specific expected results (pytz NonExistentTimeError, zoneinfo → 03:30 EDT), and a step-by-step worked assertion example with specific assertions to write.	3 / 3
Workflow Clarity	'How to use this reference' lays out a clear 4-step sequence (identify transition → match bug class → turn into assertion → pick zones + fixtures) reinforced by the worked example, with an explicit 'refresh against IANA before each release' checkpoint.	3 / 3
Progressive Disclosure	SKILL.md is an overview that cleanly signals one-level-deep detail in references/jurisdictions-and-fixtures.md via a real markdown link to a file that exists and holds the per-region rule tables and fixtures.	3 / 3
	Total	11 / 12 Passed

Description

100%

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

A highly specific, complete description with explicit 'Use when' trigger guidance and strong natural-language trigger terms. Its only weakness is verbosity — the catalog is packed into one long sentence with heavy parentheticals, but this does not reduce the scored dimensions.

Dimension	Reasoning	Score
Specificity	Lists multiple concrete capabilities: 'spring-forward (skipped hour: 02:00 → 03:00)', 'fall-back (repeated hour: 02:00 → 01:00)', 'cron jobs that fire 0 or 2 times', 'billing periods that miss / double-count', and the IANA tz database as canonical source.	3 / 3
Completeness	Explicitly answers both what ('Pure-reference catalog of DST transition patterns and their canonical bug classes') and when ('Use when designing or auditing time-handling code or test cases').	3 / 3
Trigger Term Quality	Good coverage of natural terms a user would say: 'Daylight Saving Time (DST)', 'spring-forward', 'fall-back', 'timezone', 'time-handling code', 'test cases'.	3 / 3
Distinctiveness Conflict Risk	Clear, narrow niche (DST transitions and their bug classes) with distinct triggers unlikely to fire for general time/date skills.	3 / 3
	Total	12 / 12 Passed

Validation

100%

Warnings & errors only

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Reviewed

5 days ago

Table of Contents

Discovery Implementation Validation