Conciseness

Lean and assumes Claude's competence (no explaining of Figma/shaders/WebGPU), but the isAnimated/usesMouse metadata rules appear in both the Create workflow step 6 and Authoring rules, a minor redundancy that could be trimmed.

Actionability

Concrete, specific guidance with exact tool names, parameters, file paths, and a URL template; minor gap is the absence of a complete worked example payload for the common create-then-update case.

Workflow Clarity

Both workflows are numbered with clear sequencing and explicit feedback loops — build-error retry-once-then-surface, the "Never stop after create_shader" guard, and the terminal capability gate for unavailable animation/mouse input.

Progressive Disclosure

SKILL.md is an overview with well-signaled one-level-deep reference to references/authoring.md (verified to exist, self-contained with its own TOC, no nested file references), and tells the reader exactly what that file contains.

Specificity

Lists several concrete actions ("create, author, change, fix, or iterate") across named shader types, but the verbs are request intents rather than the fully concrete operational actions of the 5 anchor.

Completeness

Explicitly answers both what ("load this skill before calling create_shader or update_shader") and when ("Use when the user asks to create, author, change, fix, or iterate on...") with concrete trigger phrases.

Trigger Term Quality

Good natural-term coverage with synonyms ("shader effect", "custom effect", "shader fill", "custom fill", "procedural shader", "in Figma"); a few natural phrasings are absent but the core triggers a user would say are present.

Distinctiveness Conflict Risk

Narrow Figma-shader niche with specific trigger terms (shader effect/fill, custom effect/fill, procedural shader) makes conflict with other skills minimal.