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writing-guidelines

Review docs/prose for Writing Guidelines compliance. Use when asked to "review my docs", "check writing style", "audit prose", "review docs voice and tone", or "check this page against the writing handbook".

63

Quality

73%

Does it follow best practices?

Impact

No eval scenarios have been run

SecuritybySnyk

Advisory

Suggest reviewing before use

Fix and improve this skill with Tessl

tessl review fix ./skills/writing-guidelines/SKILL.md
SKILL.md
Quality
Evals
Security

Security

2 findings — 2 medium severity. This skill can be installed but you should review these findings before use.

Medium

W011: Third-party content exposure detected (indirect prompt injection risk)

What this means

The skill exposes the agent to untrusted, user-generated content from public third-party sources, creating a risk of indirect prompt injection. This includes browsing arbitrary URLs, reading social media posts or forum comments, and analyzing content from unknown websites.

Why it was flagged

Third-party content exposure detected (high risk: 0.95). The skill uses WebFetch to retrieve guidelines from a public GitHub URL at runtime, and that fetched free-form text is then ingested into the agent’s LLM context to drive the review (outsider-authored public web content).

Report incorrect finding
Medium

W012: Unverifiable external dependency detected (runtime URL that controls agent)

What this means

The skill fetches instructions or code from an external URL at runtime, and the fetched content directly controls the agent’s prompts or executes code. This dynamic dependency allows the external source to modify the agent’s behavior without any changes to the skill itself.

Why it was flagged

Potentially malicious external URL detected (high risk: 1.00). The skill explicitly requires fetching runtime rules from https://raw.githubusercontent.com/vercel-labs/writing-guidelines/main/command.md and uses that fetched content to control the agent's checking logic and output format, constituting a runtime external dependency that directly controls prompts.

Repository
vercel-labs/agent-skills
Audited
Security analysis
Snyk

Is this your skill?

If you maintain this skill, you can claim it as your own. Once claimed, you can manage eval scenarios, bundle related skills, attach documentation or rules, and ensure cross-agent compatibility.