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codebase-onboarding

Analyze an unfamiliar codebase and generate a structured onboarding guide with architecture map, key entry points, conventions, and a starter CLAUDE.md. Use when joining a new project or setting up Claude Code for the first time in a repo.

Quality

84%

Does it follow best practices?

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SecuritybySnyk

Passed

No findings from the security scan

The canonical home for this skill is codebase-onboarding in affaan-m/ECC

SKILL.md
Quality
Evals
Security

Quality

Content

75%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-structured instruction-only skill: concrete reconnaissance checklists, a clearly sequenced 4-phase workflow, and complete output templates make the guidance highly actionable. The main gaps are repeated guidance across sections, missing specific commands for a few detection steps, and validation stated as principles rather than explicit phase checkpoints.

Suggestions

Add the specific commands behind the vague detection steps — e.g., `git log --oneline -20` and `git branch --sort=-committerdate` for Git conventions, and a concrete directory-snapshot command for Phase 1 — to make the guidance copy-paste ready.

Convert the "Verify, don't guess" and "Flag unknowns" principles into explicit validation checkpoints within the phase sequence (e.g., after Phase 2, cross-check the detected stack against actual imports before generating artifacts).

Trim redundancy: the intro paragraph restates the frontmatter description, and CLAUDE.md-preservation guidance appears in Phase 4, Best Practices, and Examples — consolidating these would tighten the token budget.

DimensionReasoningScore

Conciseness

The body is efficient — concrete filename checklists ("package.json, go.mod, Cargo.toml...", "ignoring node_modules, vendor, .git, dist...") with no explanations of concepts Claude already knows. Minor trimmable redundancy keeps it below 5: the intro paragraph restates the frontmatter description, and CLAUDE.md-preservation guidance is repeated three times (Phase 4, Best Practice 3, Example 3).

4 / 5

Actionability

Concrete detection targets (exact manifest, config, and test-file patterns) and copy-ready output templates give mostly executable guidance. Not 5 because process steps omit specific commands — e.g., "Branch naming from recent branches" and "Commit message style from recent commits" name no git command, and the directory snapshot gives no actual command.

4 / 5

Workflow Clarity

A clear 4-phase sequence (Reconnaissance → Architecture Mapping → Convention Detection → Generate Artifacts) with per-request routing in Examples and safeguards ("Verify, don't guess", "Flag unknowns", preserve existing CLAUDE.md). Not 5 because validation appears as principles in Best Practices rather than explicit in-sequence checkpoints or feedback loops between phases.

4 / 5

Progressive Disclosure

No bundle files exist and the ~225-line body is cleanly sectioned with templates inlined — defensible since the templates are used on every run. Good structure with minor organization gaps matches the 4 anchor; not 5 because the two full output templates (~85 lines) are split-out candidates for references/, and not 3 since nothing is buried or poorly signaled.

4 / 5

Total

16

/

20

Passed

Description

88%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 that explicitly states both what the skill produces (enumerated onboarding artifacts) and when to use it, in third person with concrete deliverables. The only gaps are a few natural trigger phrasings users would say ("onboard me", "understand this codebase") and minor overlap risk with generic CLAUDE.md-generation skills.

DimensionReasoningScore

Specificity

"generate a structured onboarding guide with architecture map, key entry points, conventions, and a starter CLAUDE.md" enumerates multiple concrete deliverables that comprehensively cover the skill's outputs. Not 4 because coverage of what the skill produces is complete rather than gappy; the leading verb "Analyze an unfamiliar codebase" is generic but the enumerated artifacts make the capability concrete.

5 / 5

Completeness

Explicitly answers both: what — "Analyze an unfamiliar codebase and generate a structured onboarding guide with architecture map, key entry points, conventions, and a starter CLAUDE.md"; when — "Use when joining a new project or setting up Claude Code for the first time in a repo". Both are concrete and explicit, matching the 5 anchor; not 4 because the when-clause names specific triggering situations rather than being generic.

5 / 5

Trigger Term Quality

Natural terms present include "unfamiliar codebase", "joining a new project", "setting up Claude Code", and "first time". Missing common user phrasings like "onboard me", "help me understand this codebase", or "walk me through this repo" (which the body's When to Use section itself lists), so keyword coverage is good but not synonym-complete as the 5 anchor requires.

4 / 5

Distinctiveness Conflict Risk

The onboarding-analysis niche ("architecture map", "key entry points", "unfamiliar codebase") is mostly distinct, but "a starter CLAUDE.md" and "setting up Claude Code for the first time in a repo" overlap with CLAUDE.md-generation/init-style skills. Minor overlap risk with closely related skills matches the 4 anchor; not 5 because of that overlap.

4 / 5

Total

18

/

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

valeriibeck-star/claude-skills

Path

skills/codebase-onboarding/SKILL.md

Reviewed

Table of Contents

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