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testland/cli-output-conventions

Conventions for designing AND testing CLI output so it stays parseable and assertable - exit-code policy (0 success, non-zero failure with stable codes per failure mode), `stdout` for primary data / `stderr` for messages, `--json` / `--plain` for machine-readable output, deterministic ordering and timestamps, `NO_COLOR` / TTY-aware color, `-q` / `--verbose` discipline, and stable `--help` / `--version`. Built on the [Command Line Interface Guidelines][clig]. Use as the assertion contract for `bats-testing` (text CLIs) and to tell `tui-snapshot-tester` what does NOT need a snapshot.

80

Quality

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Overview
Quality
Evals
Security
Files

Quality

Content

100%

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

A well-engineered instruction skill: concise convention statements backed by executable bats test patterns, a useful anti-patterns table, honest limitations, and a correctly split one-level reference file. It respects Claude's competence while providing concrete, copy-paste-ready assertions.

DimensionReasoningScore

Conciseness

The body is lean: short convention sections each followed by a tight executable bats snippet, an anti-patterns table, and a brief limitations list. The clig blockquotes are brief authoritative citations rather than pedagogical padding, so every token earns its place; not a 2 because there is no teach-the-basics bloat.

3 / 3

Actionability

Each convention ships copy-paste-ready bats assertions (e.g. "run --separate-stderr mycli list", "[ \"$status\" -eq 2 ]", "echo \"$output\" | jq -e ...") plus concrete good/bad shell transcripts, matching the 'fully executable code/commands; copy-paste ready' anchor.

3 / 3

Workflow Clarity

Sequencing is explicit via the "When to use" section and per-convention test patterns; for a convention/contract skill (single-purpose, non-destructive) the guidance is unambiguous. Per the simple-skills scoring note, an unambiguous single-purpose skill can score 3 without destructive-op validation checkpoints.

3 / 3

Progressive Disclosure

SKILL.md is an overview with conventions 1-4 inline and conventions 5-8 clearly signaled via a one-level-deep reference to references/conventions-5-8.md (a real file). Organization is clean with easy navigation, matching the 'clear overview with well-signaled one-level-deep references' anchor.

3 / 3

Total

12

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12

Passed

Description

100%

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 high-quality description: third-person voice, comprehensive concrete capabilities, explicit natural-language triggers, and clear delineation from sibling skills. It satisfies all four dimensions at the top anchor without verbosity or over-claiming.

DimensionReasoningScore

Specificity

Lists multiple concrete actions/policies — "exit-code policy", "stdout for primary data / stderr for messages", "--json / --plain", "deterministic ordering and timestamps", "NO_COLOR / TTY-aware color", "-q / --verbose", "stable --help / --version" — each tied to a concrete behavior, matching the 'lists multiple specific concrete actions' anchor. Not a 2 because coverage is comprehensive rather than partial.

3 / 3

Completeness

Explicitly answers both what (the conventions enumerated) and when via the "Use when designing or testing a CLI's output - a new flag, command, or error message, writing CLI assertions, or fixing flaky tests..." clause, matching the 'clearly answers both what AND when with explicit triggers' anchor.

3 / 3

Trigger Term Quality

Natural user-facing triggers are present and varied: "designing or testing a CLI's output", "a new flag, command, or error message", "writing CLI assertions", "fixing flaky tests caused by non-deterministic output". These are phrases a user would naturally say, matching the 'good coverage of natural terms' anchor; not a 2 because common variations are well covered.

3 / 3

Distinctiveness Conflict Risk

Has a clear niche (CLI output contract) and explicitly delineates from sister skills — "assertion contract for bats-testing and tells tui-snapshot-tester what does NOT need a snapshot" — making conflict unlikely, matching the 'clear niche with distinct triggers' anchor.

3 / 3

Total

12

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12

Passed

Validation

100%

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

Validation16 / 16 Passed

Validation for skill structure

No warnings or errors.

Reviewed

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