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aws-cloudformation

Author, validate, and troubleshoot AWS CloudFormation templates. Covers template authoring with secure defaults, pre-deployment validation (cfn-lint, cfn-guard, change sets), and root-cause diagnosis of failed stacks using CloudFormation events and CloudTrail correlation.

Quality

80%

Does it follow best practices?

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SecuritybySnyk

Passed

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tessl review fix ./.kiro/skills/aws-cloudformation/SKILL.md
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.

A well-engineered skill body: a concise overview that defers detailed SOPs to real, purpose-labeled reference files, with exact commands, explicit validation layers, and a genuinely instructive failure-diagnosis workflow. The only minor issues are a thrice-repeated API warning and deferral of tool invocations to the referenced SOPs.

DimensionReasoningScore

Conciseness

The body assumes Claude's competence — no basic CloudFormation explanations, just deltas like "PublicAccessBlockConfiguration (all four true)" and "DeletionPolicy: Retain" — and every section carries actionable weight. Not 5: the describe-stack-events warning is repeated three times (validation, troubleshooting key points, and the troubleshooting table), a minor redundancy that could be consolidated.

4 / 5

Actionability

Concrete, near copy-paste commands are given ("aws cloudformation describe-events --change-set-id <arn> --region <region>", "--filters FailedEvents=true"), plus specific secure defaults and a "!Sub "${AWS::StackName}-..."" pattern. Not 5: the actual cfn-lint/cfn-guard invocations for the 3-layer pipeline are deferred to the referenced SOPs rather than shown, leaving minor gaps in the top-level guidance.

4 / 5

Workflow Clarity

The validation pipeline is an explicit, ordered, three-layer checkpoint sequence; troubleshooting walks through root-cause analysis (examine EVERY ResourceStatusReason, distinguish real failures from rollback cascades, enumerate all permission gaps, warn about latent failures on retry) and ends with a template-level vs environment-level fix classification. This matches the anchor's "explicit validation steps; feedback loops for error recovery; checklists" — the authoring task references a review-checklist SOP and the cascade warning covers the next-iteration loop.

5 / 5

Progressive Disclosure

The body is a lean ~80-line overview with six clearly signaled one-level-deep references, all of which exist in references/, each link stating its purpose ("as a review checklist", "to verify against authoritative documentation"). Navigation is further aided by a decision-guide table and a symptom/cause/action troubleshooting table, matching the top anchor for structure and easy navigation.

5 / 5

Total

18

/

20

Passed

Description

71%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 specific, well-scoped description that concretely covers the full CloudFormation lifecycle with named tooling and no fluff. Its main weakness is the absence of an explicit "Use when..." trigger clause, which both caps completeness and leaves some natural trigger phrases (IaC, YAML/JSON, stack stuck/rollback) unsurfaced.

Suggestions

Add an explicit trigger clause, e.g. "Use when working with CloudFormation templates (YAML/JSON), before deploying stacks, or when a stack fails, rolls back, or is stuck."

Include common user phrasings and synonyms such as "infrastructure as code", "stack deployment failed", "rollback", and "change set review" to broaden natural trigger coverage.

Optionally note the boundary explicitly in the description (e.g. "for CDK apps use a CDK skill") to reduce overlap risk with closely related IaC skills.

DimensionReasoningScore

Specificity

"Author, validate, and troubleshoot AWS CloudFormation templates" plus per-stage specifics — "secure defaults", "cfn-lint, cfn-guard, change sets", "root-cause diagnosis of failed stacks using CloudFormation events and CloudTrail correlation" — lists multiple concrete actions with comprehensive lifecycle coverage. Not 4: coverage spans all three lifecycle stages with concrete tooling, leaving no notable gaps.

5 / 5

Completeness

The "what" is clearly and concretely answered (authoring, validation, troubleshooting with named tools), but there is no "Use when..." clause or equivalent explicit trigger guidance — the judging guideline caps completeness at 3 for this. Not 4: the "when" is not merely imprecise, it is entirely implicit in the domain naming.

3 / 5

Trigger Term Quality

Good natural keywords ("CloudFormation templates", "validate", "failed stacks", "troubleshoot") that users would naturally say, but common variations like YAML/JSON, "infrastructure as code"/IaC, "stack stuck", or "rollback" are absent. Not 5: the anchor expects comprehensive synonym coverage, which is not met; not 3: the terms present go well beyond a single generic keyword.

4 / 5

Distinctiveness Conflict Risk

The description is firmly anchored to CloudFormation-specific artifacts (cfn-lint, cfn-guard, change sets, CloudTrail), making it mostly distinct with minimal conflict risk. Not 5: phrases like "diagnosis of failed stacks" and "template authoring" have minor overlap with closely related CDK/Terraform IaC skills, matching the anchor-4 example of minor overlap with closely related skills.

4 / 5

Total

16

/

20

Passed

Validation

81%

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

Validation — 13 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

metadata_version

'metadata.version' is missing

Warning

metadata_field

'metadata' should map string keys to string values

Warning

frontmatter_unknown_keys

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

Warning

Total

13

/

16

Passed

Repository

mreferre/aws-agent-toolkit-skills

Path

.kiro/skills/aws-cloudformation/SKILL.md

Reviewed

Table of Contents

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