Variant Analysis: Locate a Bug and Eliminate All Similar Ones
Trail of Bits’ variant-analysis has turned the daily variant analysis work of security engineers into an Agent Skill: after confirming a vulnerability, it extracts the root cause, calibrates with precise patterns, searches the entire codebase while relaxing only one condition at a time, and finally triages and leaves CI rules. This article explains the five-step workflow, the selection of ripgrep, Semgrep and CodeQL, as well as the installation and invocation methods of Claude Code, Codex and Cursor, based on the official SKILL.md, plugin README and policy documents.
Read MoreSemgrep-Rule-Creator: Using Agent to Write Testable Semgrep Security Rules
`semgrep-rule-creator` is an Agent Skill launched by Trail of Bits, used to create custom Semgrep rules that can detect security vulnerabilities, bug patterns and code patterns. Instead of running existing rule sets, it forces the Agent to produce rules following the workflow of test-first, AST analysis, priority given to taint mode, and optimization only after all tests pass. This article organizes the installation method, seven-step workflow, eval taint example and usage boundaries based on the official SKILL.md, plugin README and skill market description.
Read More# Property-Based Testing: Trail of Bits Turns Property Testing into Reusable Agent Skills
Trail of Bits' property-based-testing is a cross-language skill guide for property testing that includes smart contracts. It teaches agents to identify encoding/decoding, parsing, normalization, and contract invariants, write tests based on properties like round-trip and idempotence, and distinguish between test errors and real bugs when tests fail. Based on the official SKILL.md, plugin READMEs and market repositories, the article explains the installation of Claude Code / Codex, the `npx skills add` command, and reproducible examples such as Hypothesis.
Read MoreDifferential Review: Trail of Bits formalizes PR security differential review into an executable workflow
Differential-review is an Agent Skill released by Trail of Bits, which conducts security-focused reviews on PRs, commits and diffs: it classifies tasks by risk rather than line count, uses git history to detect regressions, quantitatively calculates the blast radius, treats missing tests as a higher risk factor, and enforces the output of a Markdown report with line numbers and attack scenarios. This article checks the official SKILL.md, plugin README and documentation website, explaining what problems it solves, how to install it in Claude Code / Codex / the general Skill catalog, as well as three official usage scenarios and inapplicable scenarios.
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