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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

68%

Does it follow best practices?

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SecuritybySnyk

Passed

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

Quality

Content

87%

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

The body is concise, actionable, and well-structured with executable code and commands throughout. Its main gap is the absence of explicit validation/checkpoint steps in the build-and-test workflow, which caps workflow clarity at 2.

Suggestions

Add a validation checkpoint to the Build & Test workflow, e.g. 'Confirm `cargo build` succeeds with no errors before running the command; if compilation fails, fix custom.rs and rebuild.'

Include a brief error-recovery note for common failures (e.g. SDK method renamed by regeneration) to close the fix→retry feedback loop referenced in the Regeneration Safety section.

Optionally show a one-line check that the registered command appears (e.g. `null-type --help`) so users can verify registration before invoking it.

DimensionReasoningScore

Conciseness

The body is lean and assumes Claude's competence — it never explains what a CLI, Rust, or cargo is, and dense lines like 'inherits the CLI's auth, retries, TLS, base URL, and global headers' earn their tokens, matching 'lean and efficient; every token earns its place'.

3 / 3

Actionability

Provides fully executable Rust (the complete register() handler) plus copy-paste build/test commands ('cargo build', 'null-type get <id>') and concrete patterns (super::sdk::client(ctx), super::sdk::block_on(...)), matching 'fully executable code/commands; copy-paste ready'.

3 / 3

Workflow Clarity

Steps are clearly sequenced (1. Edit custom.rs, 2. SDK clients, 3. Key patterns) but the build/test section lists commands with no validation checkpoint or fix-and-retry feedback loop, matching 'steps listed but validation gaps; checkpoints missing or implicit'.

2 / 3

Progressive Disclosure

No bundle files exist and the body references nothing external, yet it is well-organized into clearly labeled sections with no monolithic wall or nested references, satisfying the guideline that self-contained, well-organized skills can score 3 on progressive disclosure.

3 / 3

Total

11

/

12

Passed

Description

50%

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 concisely states what the skill does but lacks any explicit 'Use when...' trigger guidance, which caps its completeness. Trigger-term coverage is thin and the domain reference leans on a niche product name rather than natural user phrasing.

Suggestions

Add an explicit trigger clause, e.g. 'Use when extending the null-type CLI with hand-written commands or wiring SDK calls into custom CLI subcommands.'

Expand the action list to concrete verbs a user would recognize, e.g. 'register, build, and test custom CLI commands that call the co-generated typed SDK.'

Include natural trigger terms users would actually say (e.g. 'custom CLI command', 'add null-type subcommand', 'call the SDK from a handler') to improve trigger-term quality.

DimensionReasoningScore

Specificity

Names a concrete domain and action ("author custom commands for the null-type CLI using the co-generated SDK") but does not enumerate multiple specific actions, so it lands at 'names domain and some actions, not comprehensive' rather than listing several concrete actions.

2 / 3

Completeness

Clearly states what the skill does (authoring custom commands) but provides no 'Use when...' trigger guidance, which per the guidelines caps completeness at 2 ('has what, but when is missing or only implied').

2 / 3

Trigger Term Quality

Contains some relevant keywords ("custom commands", "CLI") but offers no natural trigger variations a user would actually say, so it matches 'some relevant keywords but missing common variations'.

2 / 3

Distinctiveness Conflict Risk

Being scoped to the niche 'null-type' CLI gives it some specificity, yet 'custom commands' and 'CLI' could still overlap with other CLI-authoring skills, matching 'somewhat specific but could still overlap'.

2 / 3

Total

8

/

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.

Repository
fern-api/fern
Reviewed

Table of Contents

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