fp-either-ref

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

Quality

76%

Does it follow best practices?

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Passed

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tessl review fix ./skills/fp-either-ref/SKILL.md

Quality

Content

100%Scale 1-5

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

This is an excellent quick reference skill that is lean, actionable, and well-structured. It provides executable TypeScript examples covering all common Either operations without any unnecessary explanation. The progression from basic API to patterns to comparison with try/catch is logical and complete for a reference card.

Dimension	Reasoning	Score
Conciseness	Every token earns its place. No unnecessary explanations of what Either is beyond the one-line summary. Assumes Claude knows TypeScript and fp-ts concepts. The API reference is terse and well-organized.	5 / 5
Actionability	All code examples are executable TypeScript with proper imports. Covers creation, transformation, extraction, and common patterns with copy-paste ready code. The comparison with try/catch provides concrete before/after examples.	5 / 5
Workflow Clarity	This is a single-purpose reference skill (API quick reference), not a multi-step workflow. The sections are logically sequenced from creation → transformation → extraction → patterns → comparison, which is clear and intuitive for a reference card.	5 / 5
Progressive Disclosure	For a concise quick reference under 50 lines with no need for external files, the content is well-organized into clearly labeled sections (Create, Transform, Extract, Common Patterns, vs try/catch). No bundle files are needed for this scope.	5 / 5
	Total	20 / 20 Passed

Description

53%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 correctly identifies the domain (Either type) and includes a 'Use when' clause, which is good. However, it lacks concrete actions or specific capabilities (e.g., pattern matching, chaining, converting between types), and the trigger terms are somewhat generic, risking overlap with other error-handling skills. The 'what' portion is essentially just 'quick reference' without detailing what the reference covers.

Suggestions

Add specific concrete actions the skill covers, e.g., 'Covers creating Either values, pattern matching on Left/Right, chaining with flatMap, converting to Option/Result'.

Include more natural trigger terms and synonyms users might use, such as 'Left/Right', 'Result type', 'functional error handling', or the specific programming language this applies to.

Expand the 'when' clause with more specific trigger scenarios, e.g., 'Use when user asks about Either, Left/Right types, or wants to handle errors without exceptions'.

Dimension	Reasoning	Score
Specificity	Names the domain ('Either type') but provides no concrete actions. 'Error handling, validation, or operations that can fail' are generic descriptions of the domain rather than specific capabilities like 'chain computations with flatMap, pattern match on Left/Right, convert to Option'.	2 / 5
Completeness	Has both 'what' ('Quick reference for Either type') and 'when' ('Use when user needs error handling, validation, or operations that can fail with typed errors'). The 'when' clause is present and reasonably explicit, though the 'what' is quite thin — 'quick reference' doesn't describe specific actions or content.	4 / 5
Trigger Term Quality	Includes some relevant keywords like 'Either type', 'error handling', 'validation', and 'typed errors', but misses natural terms users might say such as 'Left', 'Right', 'Result type', 'functional error handling', 'map/flatMap', or specific language references (e.g., Scala, Kotlin, TypeScript).	3 / 5
Distinctiveness Conflict Risk	'Error handling' and 'validation' are very broad terms that could overlap with many other skills (e.g., try/catch error handling, form validation, Result types). The 'Either type' mention adds some specificity, but 'operations that can fail with typed errors' could match other error-handling patterns.	3 / 5
	Total	12 / 20 Passed

Validation

90%

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 — 10 / 11 Passed

Validation for skill structure

Criteria	Description	Result
frontmatter_unknown_keys	Unknown frontmatter key(s) found; consider removing or moving to metadata	Warning

	Total	10 / 11 Passed

Repository: administrakt0r/AI-Agents-Safe-Coding-Skills
Path: skills/fp-either-ref/SKILL.md
Commit: 56bf65c

Reviewed: ~5 hours ago

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