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api-design-principles

Master REST and GraphQL API design principles to build intuitive, scalable, and maintainable APIs that delight developers and stand the test of time.

43

Quality

44%

Does it follow best practices?

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SecuritybySnyk

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tessl review fix ./skills/antigravity-api-design-principles/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

40%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.

The body is concise and well-sectioned but hollow: the workflow is four abstract directives with no concrete, executable guidance, and progressive disclosure is broken — it points to a nonexistent 'resources/implementation-playbook.md' while leaving the four substantial bundle files (REST best practices, GraphQL schema design, an API checklist, and a FastAPI template) entirely unlinked. The main fixes are to correct the reference path to the real files and to make each instruction step concrete.

Suggestions

Fix the broken reference: replace "resources/implementation-playbook.md" with the actual bundle paths (references/rest-best-practices.md, references/graphql-schema-design.md, assets/api-design-checklist.md, assets/rest-api-template.py), each with a one-line description of when to consult it.

Make the four instruction steps actionable — e.g., 'List consumers and their use cases', 'Prefer REST for resource-centric CRUD, GraphQL for client-driven querying', 'Specify error format (RFC 9457 problem details), cursor pagination, and versioning strategy' — or inline one short concrete example per step.

Add an explicit validation checkpoint after step 3, e.g., 'Review the spec against assets/api-design-checklist.md before implementation', to give the workflow a real feedback loop instead of the implicit 'Validate with examples'.

DimensionReasoningScore

Conciseness

The body is lean — it assumes Claude's knowledge, explains no basic concepts, and uses tight sectioning (Use when / Do not use when / Instructions / Resources / Limitations). Minor trimmable redundancy keeps it below anchor 5: the frontmatter description sentence is repeated verbatim under the H1, the reference to the playbook is stated twice (in Instructions and again in Resources), and the Limitations boilerplate adds little.

4 / 5

Actionability

The Instructions are high-level hints — "Define consumers, use cases, and constraints" and "Choose API style and model resources or types" — with no concrete commands, examples, decision criteria, or code in the body; the promised detail lives in a reference file. This matches 'minimal concrete guidance; high-level hints but missing the specific steps to execute' — above anchor 1 only because the steps do name specific concerns (errors, versioning, pagination, auth) that narrow the direction.

2 / 5

Workflow Clarity

A rough four-step sequence exists (define → choose → specify → validate) but each step is a single vague directive with no expansion, and validation is only the implicit 'Validate with examples and review for consistency' with no checkpoints or error-recovery guidance. This is 'rough sequence present but many gaps; steps poorly defined; validation absent' — short of anchor 3, whose example steps are concrete and include a real test step.

2 / 5

Progressive Disclosure

The body's only reference, "resources/implementation-playbook.md", does not exist in the bundle, while the four real bundle files (references/rest-best-practices.md, references/graphql-schema-design.md, assets/api-design-checklist.md, assets/rest-api-template.py) are never mentioned — so navigation to the actual detailed material is broken and those files are undiscoverable. Section structure itself is good, keeping this above anchor 1, but the incorrect reference path and completely unsurfaced bundle content fit 'minimal structure; references are buried' rather than anchor 3's 'references present but not clearly signaled'.

2 / 5

Total

10

/

20

Passed

Description

48%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 clearly identifies its domain (REST/GraphQL API design) but is written as marketing copy rather than a capability statement: no concrete actions, no 'Use when' trigger clause, and buzzword padding. It would benefit most from stating specific capabilities and explicit trigger conditions.

Suggestions

Replace abstract phrasing with 2-3 concrete capabilities, e.g., 'Design REST resources and URL structures, GraphQL schemas and mutations, and error/versioning/pagination/auth contracts.'

Add an explicit trigger clause, e.g., 'Use when designing or refactoring REST or GraphQL APIs, reviewing API specs, or setting team API standards.'

Cut the fluff phrases 'delight developers' and 'stand the test of time' and add natural trigger synonyms like 'endpoints' and 'API contract' to improve trigger-term coverage.

DimensionReasoningScore

Specificity

The description names the domain ("REST and GraphQL API design principles") but the only actions are the generic "build... APIs"; there are no concrete capabilities (e.g., designing endpoints, error contracts, pagination, schema modeling), and phrases like "delight developers and stand the test of time" are pure fluff. It is above anchor 1 because the domain is clearly named, but below anchor 3 because no concrete, specific actions are listed.

2 / 5

Completeness

There is a recognizable 'what' (master API design principles to build APIs) but absolutely no 'when' — the description lacks any 'Use when...' clause or equivalent trigger guidance, which per the judging guidelines caps completeness at 3. It is above anchor 2 because the 'what' is stated rather than vague, but below anchor 4 because the 'when' is entirely absent rather than merely imprecise.

3 / 5

Trigger Term Quality

"REST", "GraphQL", and "API design" are natural terms a user would say, giving some relevant keywords. However common variations are missing — no "endpoints", "API contract", "schema", "versioning", "pagination", or any 'Use when' trigger phrasing — so it matches 'some relevant keywords but missing common variations or synonyms' rather than anchor 4's 'good keyword coverage'.

3 / 5

Distinctiveness Conflict Risk

"REST and GraphQL API design" carves out a mostly distinct niche with low conflict risk against unrelated skills, matching 'mostly distinct; minor overlap risk' (e.g., with general backend or API-documentation skills). It falls short of anchor 5 because, without any explicit trigger phrases, the broad tail "maintainable APIs that delight developers" leaves minor overlap with adjacent skills.

4 / 5

Total

12

/

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
boisenoise/skills-collections
Reviewed

Table of Contents

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