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bun-ffi

This skill should be used when the user asks about "bun:ffi", "foreign function interface", "calling C from Bun", "native libraries", "dlopen", "shared libraries", "calling native code", or integrating C/C++ libraries with Bun.

61

Quality

73%

Does it follow best practices?

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SecuritybySnyk

Passed

No findings from the security scan

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tessl review fix ./plugins/bun/skills/bun-ffi/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

78%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 content is a strong, action-oriented reference with executable examples across the FFI surface area, hurt mainly by dangling references to non-existent files and minor verbosity from repeated imports.

Suggestions

Create references/type-mappings.md and references/performance.md (or remove the 'When to Load References' section) so the signaled references are not dead links.

Consolidate the repeated 'import { ... } from "bun:ffi"' boilerplate into one stated import and reference it, to reduce token overhead.

Add an explicit validation/error-handling step to the SQLite or pointer examples (e.g., checking sqlite3_open return code) to give a concrete feedback loop.

DimensionReasoningScore

Conciseness

The body is mostly lean executable code with brief comments, but repeated import boilerplate in every section and the full FFIType enumeration are minor instances that could be trimmed.

4 / 5

Actionability

Copy-paste-ready TypeScript examples cover the common cases (dlopen, types, strings, pointers, structs, callbacks, a full SQLite walkthrough), giving concrete executable guidance throughout.

5 / 5

Workflow Clarity

The core load-define-call-free pattern is clear and the Common Errors table offers recovery guidance, but there are no explicit validation checkpoints or feedback loops in the example workflows.

4 / 5

Progressive Disclosure

Sections are well-organized and the two references are clearly signaled with trigger conditions, but those referenced files (references/type-mappings.md, references/performance.md) do not exist, so navigation is broken and a large amount of reference material is inlined.

3 / 5

Total

16

/

20

Passed

Description

67%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 excels at trigger-term coverage and distinctiveness, naming the bun:ffi niche unambiguously, but it frames everything as 'use when' triggers without a clean declarative statement of what the skill does.

Suggestions

Lead with a declarative capability statement (e.g., 'Calls native C/C++ libraries from JavaScript via Bun's FFI') before the trigger clause so 'what' is explicit.

Add natural file-extension triggers like '.so', '.dylib', '.dll' to round out the trigger terms.

DimensionReasoningScore

Specificity

The description is entirely a trigger list ('calling C from Bun', 'native libraries', 'dlopen') and never names concrete capabilities as actions, so it only identifies the domain with minimal/generic action phrasing rather than listing specific operations.

2 / 5

Completeness

The 'when' is explicit and thorough ('This skill should be used when the user asks about...'), but the 'what' is only weakly implied through trigger phrases rather than stated as a declarative capability, so it does not reach the both-explicit level.

3 / 5

Trigger Term Quality

Comprehensive coverage of natural trigger terms including the exact module name 'bun:ffi', 'foreign function interface', 'dlopen', 'shared libraries', 'calling C from Bun', and 'integrating C/C++ libraries', giving users many natural phrasings.

5 / 5

Distinctiveness Conflict Risk

The exact module token 'bun:ffi' and 'calling C from Bun' carve out a clear niche tied to a specific runtime, giving minimal conflict risk with other skills.

5 / 5

Total

15

/

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

referenced_paths_exist

Referenced path issues: 2 missing

Warning

Total

15

/

16

Passed

Repository
secondsky/claude-skills
Reviewed

Table of Contents

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