Conciseness

Nearly every sentence carries tool-specific constraints Claude cannot know (24,000-char limits, patch-batch semantics, QuickJS environment, event coalescing), but there is some redundancy — environment prohibitions stated twice ('There is no document, window, fetch...' followed by 'Do not use querySelector, addEventListener, setTimeout...') and handler-registration guidance repeated across sections — keeping it at anchor 4 rather than 5.

Actionability

Two complete, copy-paste-ready JSON documents with fully working JavaScript, an exact API code block, and precise field limits (character counts, 512-element/64-control caps, ID rules) cover the common cases, matching the fully-executable anchor 5.

Workflow Clarity

Steps 1–6 are explicitly sequenced with a validation feedback loop: VIEW_ERROR results are enumerated with instructions to fix and re-call the tool, corrections are capped at one attempt, and there is an explicit fallback ('finish with the standalone answer and explain the limitation'), matching anchor 5.

Progressive Disclosure

The skill has clear section headers but is a single ~103-line file with no bundle files; the detailed 'Exact input and supported API' limits and the 'Styling' reference are inlined in SKILL.md where a one-level-deep reference file would fit, matching anchor 3 ('content that should be separate is inline') rather than 4.

Specificity

Concrete actions are named — 'Show an interactive calculator, simulator or comparison directly in the conversation' — with an explicit disambiguation ('Prefer it to writing an HTML file unless the user asks for a file, page or project code'), but coverage of the tool's full surface (title/summary/html/css/javascript inputs) is incomplete, matching anchor 4 rather than 5.

Completeness

It explicitly answers both 'what' (show an interactive calculator, simulator or comparison in the conversation) and 'when' ('when the user wants to adjust inputs and see results, such as splitting a bill, comparing plans or exploring parameters') with concrete trigger phrases and a boundary clause, matching anchor 5 exactly.

Trigger Term Quality

Natural user phrases like 'adjust inputs and see results', 'splitting a bill', 'comparing plans' and 'exploring parameters' give good coverage, but common variants such as 'what-if' or 'try different numbers' appear only in the body, not the description, so it falls short of comprehensive synonym coverage (anchor 5).

Distinctiveness Conflict Risk

It carves out a clear niche — an interactive in-conversation view — and explicitly contrasts it with the nearest competing behavior (writing an HTML file unless the user asks for a file, page or project code), giving distinct triggers with minimal conflict risk as in anchor 5.