sharp-edges

An agent skill by trailofbits, from trailofbits/skills. Tags: api, design, security, validation.

What it does

Identifies error-prone APIs, dangerous configurations, and footgun designs that enable security mistakes. Use when reviewing API designs, configuration schemas, cryptographic library ergonomics, or evaluating whether code follows 'secure by default' and 'pit of success' principles. Triggers: footgun, misuse-resistant, secure defaults, API usability, dangerous configuration.

Install

With the skills CLI, which installs into Claude Code, Codex, Cursor and other agents:

npx skills add trailofbits/skills --skill sharp-edges

Or copy the skill folder into Claude Code's skills directory by hand (~/.claude/skills for every project, or .claude/skills inside one):

git clone --depth 1 https://github.com/trailofbits/skills
cp -r skills/plugins/sharp-edges/skills/sharp-edges ~/.claude/skills/sharp-edges

Safety box score

Grade A, minimal risk: 0 of 100 risk points, rated 2026-10-20. The grade rates what the skill and its scripts can reach on the machine of whoever installs it, across eight categories from shell execution to secrets access. How the score works.

This skill is a read-only analysis pack: it ships markdown references, one YAML descriptor, and an SVG, with no scripts, downloads, or code execution paths. The main content risk is educational examples of dangerous APIs and commands, but they are examples only and not operational behavior.

Category levels, from 0 (none) to 3 (high)
Category	Level	Why
Code & shell execution	0 (none)	`allowed-tools: Read Grep Glob` and the repo contains only Markdown/YAML/SVG files; there are no shell scripts or evaluable code paths.
Network access	0 (none)	No file references a downloader, API client, or remote fetch behavior; the only URL is the repository URL in the user prompt, not in the skill itself.
Filesystem reach	0 (none)	The skill does not write or delete files; its purpose is analysis, and the shipped files are read-only documentation.
Secrets & credentials	0 (none)	It does not request tokens, passwords, `.env` files, or credential stores, and there is no secret-handling logic in the skill files.
Privilege & persistence	0 (none)	No sudo, service registration, shell startup edits, or global installs are present; `agents/openai.yaml` only defines UI metadata.
Instruction hijack surface	0 (none)	The text gives analysis guidance only; it does not tell the agent to ignore instructions, hide actions, or follow fetched remote content.
Irreversible actions	0 (none)	The skill analyzes APIs/configs and does not push, deploy, send messages, or otherwise act on external systems.
Transparency	0 (none)	All shipped assets are human-readable markdown/YAML/SVG; there are no binaries, minified blobs, or generated installers.

Before installing

Verify the package still contains only the listed markdown/YAML/SVG files and no added scripts or installers.
Confirm the agent that uses this skill is limited to read-only tools (as declared: Read, Grep, Glob).
If you later add examples or references, keep them local and human-readable; avoid remote includes or executable snippets.

Rated 2026-10-20 by an automated review of 19 files from the skill's repository.

Source

Repository: trailofbits/skills (all skills from this repository)
Path: plugins/sharp-edges/skills/sharp-edges/SKILL.md
Branch: main
Collection: sharp-edges
Updated: 2026-09-19

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