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fp-either-ref

Quick reference for Either type. Use when user needs error handling, validation, or operations that can fail with typed errors.

Quality

79%

Does it follow best practices?

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tessl review fix ./plugins/AI-Agents-Safe-Coding-Skills-claude/skills/fp-either-ref/SKILL.md

The canonical home for this skill is fp-either-ref in administrakt0r/AI-Agents-Safe-Coding-Skills

SKILL.md
Quality
Evals
Security

Quality

Content

85%Weight 40%Scale 1-5

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

An exemplary lean quick reference: executable, correct fp-ts code organized into scannable sections with useful common patterns and a crisp when-to-use rule. The only deductions are minor — a trimmable try/catch anti-pattern block and one snippet referencing an unimported `identity` helper.

DimensionReasoningScore

Conciseness

The body is lean and code-first with a one-line intro and terse section comments. It falls just short of 5 because the ❌ try/catch anti-pattern block spells out a basic concept Claude already knows and could be trimmed to the ✅ Either version plus a one-line rationale.

4 / 5

Actionability

All snippets are real, executable fp-ts code covering creation (right/left/fromNullable/tryCatch), transformation (map/mapLeft/flatMap/filterOrElse), extraction (getOrElse/match), and common validation/chaining patterns. A minor gap keeps it from 5: the "vs try/catch" example uses `identity` without importing it from 'fp-ts/function', so that snippet is not copy-paste ready.

4 / 5

Workflow Clarity

This is a single-purpose lookup reference, and the section flow (Create → Transform → Extract → Common Patterns → vs try/catch) is unambiguous, with a clear closing rule for when to use Either. No destructive or batch operations are involved, so no validation checkpoints are required; per the simple-skill guidance, a clear single-purpose skill scores 5.

5 / 5

Progressive Disclosure

A self-contained quick reference where everything belongs inline: well-organized sections, no buried or nested references, and no content that would be better split into separate files (the whole point is a single page). Navigation is trivial given the section structure.

5 / 5

Total

18

/

20

Passed

Description

65%Weight 40%Scale 1-5

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

The description has a clear, explicit trigger clause with natural terms, but the capability half is underdeveloped — it says "quick reference" without stating what the skill actually lets you do with Either. Adding concrete actions and the library name (fp-ts) would lift specificity and trigger coverage.

Suggestions

Replace "Quick reference for Either type" with concrete actions, e.g. "Create, transform, and chain fp-ts Either values (right/left, map, flatMap, getOrElse, tryCatch)."

Include natural trigger terms users would actually say: "fp-ts", "Left/Right", "Result type", or "functional error handling".

State the skill's scope concretely (API quick reference plus common validation/chaining patterns) so the "what" half matches the specificity of the "when" half.

DimensionReasoningScore

Specificity

"Quick reference for Either type" names the domain but offers no concrete actions (no create/transform/chain/extract verbs), matching the anchor "Names the domain but actions are minimal or generic". It is not a 1 because the domain (Either type, typed errors) is clearly identified, and not a 3 because no specific capability is listed.

2 / 5

Completeness

Both parts are present: the "what" ("Quick reference for Either type") and an explicit "Use when user needs error handling, validation, or operations that can fail with typed errors" trigger clause. It does not reach 5 because the "what" does not concretely state what the reference covers (creating, transforming, chaining Either values), leaving the capability side thin.

4 / 5

Trigger Term Quality

"error handling", "validation", and "operations that can fail with typed errors" are natural phrases users would say when needing this skill, giving good keyword coverage. It falls short of 5 because common variations users might say — "fp-ts", "Left/Right", "Result type", "functional error handling" — are absent.

4 / 5

Distinctiveness Conflict Risk

"Either type" and "typed errors" carve a distinct functional-programming niche unlikely to grab unrelated skills. However, the broad triggers "error handling" and "validation" create minor overlap risk with general validation or schema-library skills, keeping it below 5.

4 / 5

Total

14

/

20

Passed

Validation

93%

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

Validation — 15 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

Total

15

/

16

Passed

Repository

administrakt0r/AI-Agents-Safe-Coding-Skills

Path

plugins/AI-Agents-Safe-Coding-Skills-claude/skills/fp-either-ref/SKILL.md

Reviewed

Table of Contents

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