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posix-shell-pro

Expert in strict POSIX sh scripting for maximum portability across Unix-like systems. Specializes in shell scripts that run on any POSIX-compliant shell (dash, ash, sh, bash --posix).

47

Quality

50%

Does it follow best practices?

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SecuritybySnyk

Passed

No findings from the security scan

Fix and improve this skill with Tessl

tessl review fix ./plugins/AI-Agents-Safe-Coding-Skills-claude/skills/posix-shell-pro/SKILL.md

The canonical home for this skill is posix-shell-pro in administrakt0r/AI-Agents-Safe-Coding-Skills

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 rich in concrete, executable POSIX-sh snippets but is undermined by heavy redundancy, restated basics, no sequenced workflow with validation, and a monolithic inline structure with a dangling reference.

Suggestions

De-duplicate guidance repeated across sections (POSIX Constraints, Approach, Common Pitfalls, POSIX-Specific Best Practices) into a single canonical list to cut tokens.

Add an explicit numbered workflow with validation checkpoints for destructive operations (e.g. lint with shellcheck -s sh -> test on dash/ash -> validate output), instead of only generic instructions.

Move the Essential Tools catalog and References links into separate reference files and fix or remove the dangling 'resources/implementation-playbook.md' pointer (note: the directory is 'resources/', not the conventional 'references/').

DimensionReasoningScore

Conciseness

The ~300-line body is a padded wall of bullets restating POSIX basics Claude already knows, with heavy redundancy ('use [ not [[' and 'quote variable expansions' each repeated across POSIX Constraints, Approach, Common Pitfalls, and POSIX-Specific Best Practices), fitting the 'noticeably verbose, several padded sections' anchor.

2 / 5

Actionability

Many concrete executable fragments ('trap 'rm -f "$tmpfile"' EXIT INT TERM', 'command -v cmd >/dev/null 2>&1', 'set -- item1 item2 item3') provide mostly copy-paste-ready guidance, with minor gaps since most are fragments rather than complete scripts.

4 / 5

Workflow Clarity

No real sequenced workflow exists; the 'Instructions' section is generic ('Apply relevant best practices and validate outcomes') and destructive operations (rm -rf) lack explicit validation checkpoints, so it sits at the 'rough sequence, validation absent' anchor and is capped at 3 by the destructive-operations rule.

2 / 5

Progressive Disclosure

No bundle files exist, yet the body inlines content that belongs in separate files (Essential Tools catalog, References & Further Reading) and its sole external reference 'resources/implementation-playbook.md' points to a non-existent file, fitting the 'content that belongs in separate files is inlined' anchor.

2 / 5

Total

10

/

20

Passed

Description

61%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 a distinct POSIX-shell niche and surfaces natural trigger terms, but it lacks an explicit 'Use when...' trigger clause and states only generic actions, capping completeness and specificity at mid-range.

Suggestions

Add an explicit trigger clause, e.g. 'Use when writing or porting shell scripts that must run on dash, ash, sh, or bash --posix.'

Replace generic phrasing ('scripting for maximum portability') with concrete actions like 'write, lint with shellcheck -s sh, and port bash scripts to POSIX sh'.

Include common synonyms users say ('portable shell script', 'bourne shell', 'sh-compatible') to round out trigger-term coverage.

DimensionReasoningScore

Specificity

Names the domain and concrete target shells ('dash, ash, sh, bash --posix') but the actions themselves are generic ('scripting for maximum portability'), fitting the 'names domain and 1-2 concrete actions' anchor rather than the multiple-action anchor at 4.

3 / 5

Completeness

Has a clear 'what' (POSIX sh scripting for portability) but no 'Use when...' clause or equivalent explicit trigger guidance, which per the judging guidelines caps completeness at 3.

3 / 5

Trigger Term Quality

Good coverage of natural terms a user would say ('POSIX sh', 'shell scripts', 'dash', 'ash', 'sh', 'bash --posix'); a few synonyms (e.g. 'portable shell script', 'bourne shell') are missing, so it sits just below the comprehensive anchor at 5.

4 / 5

Distinctiveness Conflict Risk

The strict-POSIX-sh niche with named shells is clearly distinct from generic scripting skills, with only minor overlap risk via the 'bash --posix' mention, so it is mostly distinct rather than a fully clear niche at 5.

4 / 5

Total

14

/

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.

Validation15 / 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
administrakt0r/AI-Agents-Safe-Coding-Skills
Reviewed

Table of Contents

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