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null-type-custom-commands

How to author custom commands for the null-type CLI using the co-generated SDK.

60

Quality

70%

Does it follow best practices?

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SecuritybySnyk

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tessl review fix ./seed/cli/null-type/.agents/skills/custom-commands/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

82%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 highly actionable with executable code and a clear workflow, and it respects the token budget well. The main gaps are a missing validation step in the build/test flow and mild redundancy between the architecture and regeneration-safety sections.

Suggestions

Add an explicit validation checkpoint after building, e.g. 'null-type <your-command> --help' to confirm the command registered, before declaring success.

Merge or cross-reference the Architecture block and the Regeneration Safety table to remove the duplicated file listing.

Consider extracting the SDK sub-client reference table into a references/ file and linking to it from the body to tighten the overview.

DimensionReasoningScore

Conciseness

The body is lean and assumes Claude's competence (no explanation of CLI/cargo basics), but the Architecture block and the Regeneration Safety table restate overlapping file info, leaving minor trimmable redundancy short of a 5.

4 / 5

Actionability

It provides fully executable, copy-paste-ready Rust code, concrete cargo/null-type commands, and specific patterns (client(ctx), block_on) that cover the common cases, matching the top anchor.

5 / 5

Workflow Clarity

The 'Adding a Custom Command' section gives a clear numbered edit→register→build→test sequence, but lacks an explicit validation checkpoint (e.g. verifying the command appears in --help), so it sits at 'clear sequence with minor validation gaps' rather than 5.

4 / 5

Progressive Disclosure

No bundle files exist, so all content lives inline in SKILL.md; it is well-organized into clearly labeled sections, but at ~112 lines with reusable tables (SDK clients, regeneration safety) it has minor organization gaps versus a fully split structure, fitting the 'good structure, minor gaps' anchor.

4 / 5

Total

17

/

20

Passed

Description

57%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 and clearly distinct but lacks any explicit 'when to use' trigger guidance, which caps completeness. Adding a 'Use when...' clause with natural trigger phrases would lift the completeness and trigger_term_quality dimensions.

Suggestions

Append an explicit trigger clause, e.g. 'Use when the user wants to add or modify custom commands in the null-type CLI.'

Include natural user-facing terms and synonyms (e.g. 'add a command', 'extend the CLI') alongside the technical 'co-generated SDK' phrasing.

Optionally list 1-2 more concrete actions (e.g. 'register, wire up, and test custom commands') to move specificity toward comprehensive coverage.

DimensionReasoningScore

Specificity

The description names the domain (null-type CLI custom commands) and one concrete action ('author custom commands'), but offers no further actions, matching the '1-2 concrete actions, not comprehensive' anchor rather than the 'several specific actions' level 4.

3 / 5

Completeness

There is a clear 'what' (authoring custom commands for the null-type CLI) but no 'Use when...' trigger guidance, so per the judging guidelines completeness is capped at 3.

3 / 5

Trigger Term Quality

'custom commands' and 'CLI' are somewhat natural for a developer audience, but 'co-generated SDK' is technical jargon and common variations or synonyms are absent, fitting the 'some relevant keywords but missing variations' anchor.

3 / 5

Distinctiveness Conflict Risk

Naming a specific CLI ('null-type') carves out a clear niche with distinct triggers and minimal conflict risk against other skills, matching the top anchor.

5 / 5

Total

14

/

20

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.

Repository
fern-api/fern
Reviewed

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