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backend-security-coder

Expert in secure backend coding practices specializing in input validation, authentication, and API security. Use PROACTIVELY for backend security implementations or security code reviews.

38

Quality

37%

Does it follow best practices?

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SecuritybySnyk

Passed

No findings from the security scan

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tessl review fix ./.agent/skills/backend-security-coder/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

7%

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

This skill is essentially a table of contents with no substantive content of its own. It lacks any concrete code examples, specific security patterns, or actionable guidance—everything is deferred to sub-skill files that aren't provided. The main body is padded with generic instructions and redundant purpose statements that waste tokens without adding value.

Suggestions

Add at least 2-3 concrete, executable code examples for the most common security tasks (e.g., input validation with a specific framework, parameterized SQL queries, JWT authentication setup) directly in the SKILL.md.

Replace the generic instructions ('Apply relevant best practices and validate outcomes') with specific workflow steps, e.g., '1. Identify user inputs → 2. Apply validation using schema X → 3. Verify with test Y → 4. If validation fails, check Z.'

Remove redundant sections: the 'Purpose' section largely repeats the 'Use this skill when' section and the description. Consolidate into a single lean overview.

Include the bundle files (sub-skills and implementation-playbook.md) or inline the most critical security patterns so the skill is useful even without the referenced files.

DimensionReasoningScore

Conciseness

The content is verbose and redundant. It explains when to use/not use the skill in generic terms, restates the purpose multiple times, explains the difference between this skill and a security auditor (context Claude doesn't need), and includes filler phrases like 'comprehensive knowledge' and 'Masters input validation.' Much of this is padding that doesn't add actionable value.

1 / 3

Actionability

There is no concrete code, no executable examples, no specific commands, and no copy-paste ready guidance. The instructions are entirely abstract ('Apply relevant best practices and validate outcomes') with no specifics about what those practices are or how to validate. All concrete content is deferred to sub-skill files that aren't provided.

1 / 3

Workflow Clarity

The four bullet points under 'Instructions' are vague and generic ('Clarify goals, constraints, and required inputs'). There is no clear sequence for multi-step security tasks, no validation checkpoints, and no feedback loops. For a skill covering security implementations—which are inherently risky operations—this lack of workflow structure is a significant gap.

1 / 3

Progressive Disclosure

The skill does reference 10 sub-skill files and a resources/implementation-playbook.md, which shows an attempt at progressive disclosure with one-level-deep references. However, no bundle files were provided to verify these references exist, the overview itself contains no useful quick-start content, and the main file is mostly filler rather than a functional overview that stands on its own.

2 / 3

Total

5

/

12

Passed

Description

67%

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 has a solid structure with both 'what' and 'when' clauses clearly stated, which is its strongest aspect. However, it operates at a category level rather than listing concrete actions, and the trigger terms could be significantly expanded to cover the natural language users would employ when seeking security help. The domain is reasonably distinct but could benefit from sharper boundaries.

Suggestions

Add more specific concrete actions like 'sanitize user inputs against SQL injection and XSS, implement JWT/OAuth authentication flows, configure rate limiting and CORS policies'.

Expand trigger terms to include common user phrases like 'SQL injection', 'XSS', 'CSRF protection', 'password hashing', 'OAuth', 'token validation', 'vulnerability', 'secure my API'.

DimensionReasoningScore

Specificity

Names the domain (backend security) and some actions (input validation, authentication, API security, security code reviews), but these are more like categories than concrete actions. It doesn't list specific tasks like 'sanitize SQL queries, implement JWT token validation, configure CORS headers'.

2 / 3

Completeness

Clearly answers both 'what' (secure backend coding practices specializing in input validation, authentication, and API security) and 'when' (Use PROACTIVELY for backend security implementations or security code reviews), with an explicit trigger clause.

3 / 3

Trigger Term Quality

Includes some relevant keywords like 'input validation', 'authentication', 'API security', and 'security code reviews', but misses many natural user terms like 'SQL injection', 'XSS', 'CSRF', 'password hashing', 'OAuth', 'authorization', 'vulnerability', or 'secure endpoint'.

2 / 3

Distinctiveness Conflict Risk

The focus on 'backend security' provides some distinctiveness, but terms like 'authentication' and 'API security' could overlap with general API development skills or authentication-specific skills. The scope is broad enough to potentially conflict with more specialized security skills.

2 / 3

Total

9

/

12

Passed

Validation

81%

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

Validation9 / 11 Passed

Validation for skill structure

CriteriaDescriptionResult

metadata_version

'metadata.version' is missing

Warning

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

Total

9

/

11

Passed

Repository
Dokhacgiakhoa/antigravity-ide
Reviewed

Table of Contents

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