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diff-cost-projection

Analyze code diffs for infrastructure cost impact using CloudZero spend data. Detects Terraform, CDK, CloudFormation, SAM, K8s, scaling, and application code changes that affect cloud spending.

67

Quality

84%

Does it follow best practices?

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SecuritybySnyk

Low

Low-risk findings worth noting

SKILL.md
Quality
Evals
Security

Quality

Content

88%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 content is a strong, execution-ready workflow: phases are clearly sequenced with explicit goals, early-exit paths, verification steps, and copy-paste commands and API calls, while bulk detail is delegated to well-signaled reference files. The main gaps are minor: a few trimmable explanatory passages, and reference files that could not be verified within the skill directory itself.

DimensionReasoningScore

Conciseness

The body is dense with actionable, skill-specific guidance (git commands, CloudZero call parameters, estimation formulas) and assumes Claude's competence rather than explaining concepts it already knows. Not 5 because of occasional over-explanation that could be trimmed, e.g., 'This captures everything: committed changes on the branch, staged changes, and unstaged changes' and multi-sentence rationale around the 'Critical Rule' security paragraph.

4 / 5

Actionability

Guidance is fully executable: copy-paste bash for base-branch detection and diffing ('git diff "$MERGE_BASE"'), concrete tool calls with parameters (get_cost_data with group_by, granularity='daily', cost_type='real_cost'), explicit estimation formulas ('(M/N - 1) × 100%', 'hourly_price × 730'), a decision table for file classification, and a defined report structure. Not 4 because the common cases are covered with specific, ready-to-run commands and calls rather than leaving minor gaps.

5 / 5

Workflow Clarity

Seven clearly sequenced phases each with an explicit Goal, and validation checkpoints throughout: early-exit conditions ('If the diff is empty → report and stop', skip-category stop), dimension-value verification in Step 4.3 (get_dimension_values 'to confirm the exact dimension value string'), baseline-presence checks in Phase 6, and an error-recovery path ('If CloudZero queries fail... still provide the diff analysis'). The workflow is read-only analysis, so the destructive/batch validation cap does not apply. Not 4 because both the sequence and the checkpoint/feedback guidance are explicit rather than implicit.

5 / 5

Progressive Disclosure

The body acts as an overview with well-signaled, one-level-deep references placed at the point of need (cost-impact-taxonomy.md in Phase 3, service-mapping.md and dimensions-reference.md in Phase 4, output examples in Phase 7) plus a See Also section; bulk detail is appropriately split out of SKILL.md. Not 5 because the referenced files live under ${CLAUDE_PLUGIN_ROOT}/references/ and no references/ directory exists in the skill's own directory, so their presence and one-level depth cannot be verified from this bundle.

4 / 5

Total

18

/

20

Passed

Description

75%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 is specific, well-targeted, and rich in concrete technology keywords, giving it a clear niche with minimal conflict risk. Its main weakness is the missing 'Use when...' trigger clause, which leaves the activation conditions only weakly implied and caps completeness at 3.

Suggestions

Append an explicit trigger clause, e.g., 'Use when reviewing or merging changes to Terraform, CDK, CloudFormation, SAM, Kubernetes manifests, or when the user asks about cost/spend impact of a diff.'

Add natural user phrasings such as 'estimate cost', 'cloud bill', or 'budget' alongside the existing technology keywords.

Include file-extension variants (e.g., .tf, .yaml, serverless.yml) in the detection list to broaden trigger coverage.

DimensionReasoningScore

Specificity

The description lists multiple concrete actions — 'Analyze code diffs for infrastructure cost impact using CloudZero spend data' and 'Detects Terraform, CDK, CloudFormation, SAM, K8s, scaling, and application code changes' — with comprehensive coverage of the change categories the skill handles. Not 4 because the enumerated detection targets cover the domain comprehensively rather than leaving minor gaps.

5 / 5

Completeness

The 'what' is clearly stated ('Analyze code diffs for infrastructure cost impact using CloudZero spend data'), but there is no 'Use when...' clause or equivalent explicit trigger guidance — only a weak implication via 'changes that affect cloud spending'. Per the rubric guideline, a missing explicit 'when' caps completeness at 3; not 4 because the when-guidance requirement is explicitly unmet.

3 / 5

Trigger Term Quality

Good natural-term coverage: 'code diffs', 'infrastructure cost impact', 'cloud spending', 'scaling', plus concrete technology names (Terraform, CDK, CloudFormation, SAM, K8s). Not 5 because common user phrasings like 'estimate cost', 'cloud bill', 'budget', or extension variants (e.g., '.tf', '.yaml') are missing.

4 / 5

Distinctiveness Conflict Risk

It occupies a clear niche — cost impact analysis of infrastructure diffs using CloudZero spend data — with distinct trigger terms (CloudZero, Terraform, CDK, cost impact) that are unlikely to fire for unrelated skills. Not 4 because no meaningful overlap with other skill categories is apparent.

5 / 5

Total

17

/

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
Cloudzero/cloudzero-claude-marketplace
Reviewed

Table of Contents

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