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app-builder

Load before calling the apps tool. Use when the user wants to build or change an n8n App: a small web app, form, dashboard, tracker or other browser UI that n8n hosts. Also load when the conversation lists app targets or a pending app.

Quality

87%

Does it follow best practices?

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Passed

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SKILL.md
Quality
Evals
Security

Quality

Content

92%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 operational skill body: dense, constraint-focused, and tightly sequenced with validation and error-recovery loops. The only improvement space is showing one concrete example of an `apps` tool invocation alongside the prose descriptions.

DimensionReasoningScore

Conciseness

The body is lean and assumes Claude's competence: it never explains Vue, Vite, or basic web-app concepts, and every sentence carries n8n-specific constraints or procedure (e.g., "Use `npm ci`, not `npm install`: `npm install` can change `package-lock.json`, and n8n then rejects the commit"), matching the every-token-earns-its-place anchor.

5 / 5

Actionability

Concrete tool subcommands (`create`, `open`, `list`, `search`, `discard`), exact commands (`npm ci`, `npm run build`), precise rules (namespace format), and edge-case handling make the guidance mostly executable; the minor gap is that no literal example invocations of the `apps` tool are shown, leaving it just below the copy-paste-ready anchor.

4 / 5

Workflow Clarity

The five-step workflow has explicit validation ("Fix every error and build again until the build passes"), feedback loops ("On `failed`, read `diagnostics`... fix the source and commit again"), a bounded retry policy ("After three failed builds in a row, stop and explain"), and conflict recovery via `discard`, matching the top anchor.

5 / 5

Progressive Disclosure

The skill is a single self-contained file with no bundle directories, well-organized into scoped sections (capabilities, scaffold, workflow, multi-app, publishing); nothing is bulky enough to belong in a separate file, so well-organized sections suffice per the simple-skill guidance.

5 / 5

Total

19

/

20

Passed

Description

78%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.

A strong description with an explicit what/when structure and concrete trigger conditions tied to the n8n Apps niche. Its main weakness is thin action specificity ("build or change") and a few missing natural synonyms.

Suggestions

Enumerate more concrete capability verbs in the description (e.g., 'creates, edits, builds and versions n8n Apps') instead of only 'build or change'.

Add natural user synonyms such as 'create', 'make', or 'design an app/dashboard/form' to broaden trigger coverage.

Consider naming the apps tool interaction (source placed in the workspace, built and hosted by n8n) in one clause to sharpen the 'what'.

DimensionReasoningScore

Specificity

Names the domain clearly ("an n8n App: a small web app, form, dashboard, tracker or other browser UI that n8n hosts") but the action coverage is limited to two verbs ("build or change"), matching the anchor for 1-2 concrete actions rather than the several specific actions of a 4.

3 / 5

Completeness

Explicitly answers both parts: the "what" ("build or change an n8n App: a small web app, form, dashboard, tracker or other browser UI that n8n hosts") and the "when" ("Use when the user wants to build or change an n8n App... Also load when the conversation lists app targets or a pending app") with concrete trigger phrases.

5 / 5

Trigger Term Quality

Good natural-term coverage ("build", "change", "web app", "form", "dashboard", "tracker", "browser UI", "pending app") that users would plausibly say, though common synonyms like "create" or "make" are missing, keeping it below the comprehensive anchor 5.

4 / 5

Distinctiveness Conflict Risk

The n8n scoping and pending-app triggers give it a clear niche, but phrases like "build... a web app, form, dashboard" carry minor overlap risk with generic frontend/app-builder skills when n8n is not mentioned, fitting anchor 4 rather than 5.

4 / 5

Total

16

/

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

n8n-io/n8n

Path

packages/@n8n/instance-ai/skills/app-builder/SKILL.md

Reviewed

Table of Contents

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