Automated summary
Guides Solidity smart contract security best practices to prevent common vulnerabilities and apply secure development patterns.
Strengths
- Covers classic attack vectors: reentrancy, integer overflow and access control
- Applies both to writing new contracts and to auditing existing ones
- Ships with a detailed implementation playbook of concrete patterns
- Addresses audit preparation and gas optimization without sacrificing safety
Limitations
- Does not provide automated analysis tooling or formal verification
- Stays scoped to Solidity and DeFi, not other chains or languages
- Output quality depends on the contract and context the user supplies
Use it whenever you are writing, reviewing or auditing a Solidity contract or DeFi protocol.
Avoid it for work outside Solidity security, such as frontend development or general web application security.
Security analysis
SafeThe skill contains only instructional guidance about Solidity security best practices. It declares no tools, executes no commands, and does not request secrets, network access, or destructive operations. There is no meaningful execution risk.
No concerns found
How this analysis is madeExamples
Audit this Solidity contract for reentrancy, access control and overflow issues, and list each finding with severity and a fix: [paste contract]I'm building a staking contract that transfers rewards in ETH. Show me the secure Solidity pattern to avoid reentrancy and explain the checks-effects-interactions ordering.Review my ERC-20 token contract against common Solidity vulnerabilities and tell me what I should fix before sending it to a professional audit.version: 4.1.0-fractal name: solidity-security description: Master smart contract security best practices to prevent common vulnerabilities and implement secure Solidity patterns. Use when writing smart contracts, auditing existing contracts, or implementing security measures for blockchain applications.
Solidity Security
Master smart contract security best practices, vulnerability prevention, and secure Solidity development patterns.
Use this skill when
- Writing secure smart contracts
- Auditing existing contracts for vulnerabilities
- Implementing secure DeFi protocols
- Preventing reentrancy, overflow, and access control issues
- Optimizing gas usage while maintaining security
- Preparing contracts for professional audits
- Understanding common attack vectors
Do not use this skill when
- The task is unrelated to solidity security
- You need a different domain or tool outside this scope
Instructions
- Clarify goals, constraints, and required inputs.
- Apply relevant best practices and validate outcomes.
- Provide actionable steps and verification.
- If detailed examples are required, open
resources/implementation-playbook.md.
Resources
resources/implementation-playbook.mdfor detailed patterns and examples.
🧠 Knowledge Modules (Fractal Skills)
1. implementation-playbook
From the file to a first result
The download contains exactly the content displayed on this page. This copy may differ from the latest version in the source repository.
View the source and supporting filesThis download contains SKILL.md only. Any scripts, references, templates and dependencies are not included. Get the required files from the source, preserving their directory structure, before continuing.
1. Download the file
Download SKILL.mdFrom the root of a test project, save the file as .skill-downloads/solidity-security-msh3utts/SKILL.md, or use the command below. This folder is for inspecting the skill before installation.
Command for macOS/Linux or WSL: requires a POSIX shell and curl. On Windows without WSL, use the download button and create the folder manually.
mkdir -p '.skill-downloads/solidity-security-msh3utts' && curl --fail --show-error --location 'https://skills-guides.com/api/skills/solidity-security-msh3utts/download' --output '.skill-downloads/solidity-security-msh3utts/SKILL.md.part' && mv '.skill-downloads/solidity-security-msh3utts/SKILL.md.part' '.skill-downloads/solidity-security-msh3utts/SKILL.md'2. Check prerequisites
Read SKILL.md before using it. If it references scripts or external services, inspect them and prepare the required access in your test environment.
No recognized prerequisites section in this file. This does not mean it is self-contained: libraries, tools and access requirements may be mentioned elsewhere in the content or source repository.
The platforms on this page are catalog indications. The paths below follow tool documentation; they do not prove this skill has been run in those tools. No minimum tool version is confirmed for this listing.
3. Load the skill
After inspection, copy the complete folder into your project using one of the commands below, then open a new tool session. The command stops if a folder with the same name already exists: compare the files before replacing it.
Claude Code
test -f '.skill-downloads/solidity-security-msh3utts/SKILL.md' && test -s '.skill-downloads/solidity-security-msh3utts/SKILL.md' && mkdir -p '.claude/skills' && test ! -e '.claude/skills/solidity-security' && cp -R '.skill-downloads/solidity-security-msh3utts' '.claude/skills/solidity-security'Cursor
test -f '.skill-downloads/solidity-security-msh3utts/SKILL.md' && test -s '.skill-downloads/solidity-security-msh3utts/SKILL.md' && mkdir -p '.cursor/skills' && test ! -e '.cursor/skills/solidity-security' && cp -R '.skill-downloads/solidity-security-msh3utts' '.cursor/skills/solidity-security'Codex
test -f '.skill-downloads/solidity-security-msh3utts/SKILL.md' && test -s '.skill-downloads/solidity-security-msh3utts/SKILL.md' && mkdir -p '.agents/skills' && test ! -e '.agents/skills/solidity-security' && cp -R '.skill-downloads/solidity-security-msh3utts' '.agents/skills/solidity-security'OpenSkills
OpenSkills must already be installed. The local install/read procedure is checked with OpenSkills 1.5.0, which requires Node.js ≥ 20.6.0. Catalog slugs are not resolved automatically.
Official OpenSkills installationopenskills install './.skill-downloads/solidity-security-msh3utts'openskills read 'solidity-security-msh3utts'Reading should display the installed file content and its base directory. It does not run the skill or install its dependencies.
For an agent that reads AGENTS.md, then sync the index. This command changes AGENTS.md: review the diff before using it.
openskills syncManual method or another tool: attach SKILL.md to a conversation, or open it in an agent that can read files. Include any required supporting resources. No universal folder is recognized by every tool.
4. Try a first task
Use a short, synthetic input: an API endpoint, a small document or an interface brief. In a new conversation, attach the file or give the agent its path, then adapt this request:
Read .skill-downloads/solidity-security-msh3utts/SKILL.md and apply its instructions to this example: [describe a test input]. Identify any missing files, dependencies or access. Produce the result requested by the skill without inventing data or running unreviewed scripts.Expected result: output matching the skill instructions, or a precise list of missing prerequisites. A read confirmation alone does not validate a first use. If an external resource is unavailable, that path remains untested.
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