How do I install the Solidity Scanner skill?

Run npx skillmds@latest add 0x-shashi/solidity-scanner in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

What does the Solidity Scanner skill do?

Use when the user wants to audit Solidity smart contracts for security vulnerabilities, scan EVM-compatible contracts for reentrancy, oracle manipulation, access-control, or flash-loan issues, review DeFi protocols on Ethereum, Arbitrum, Optimism, Base, Polygon, or BSC, or generate security audit reports for smart contract deployments. It is listed under Security on SkillMD.

Is Solidity Scanner safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Solidity Scanner?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Solidity Scanner free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Solidity Scanner?

0x-Shashi (@0x-shashi) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Solidity Scanner by 0x-shashi — Agent Skill

Name: Solidity Scanner
Author: 0x-Shashi

Solidity Scanner Skill

Purpose

Analyze Solidity smart contracts for security vulnerabilities across all EVM-compatible chains. This is the primary scanner for the most widely-deployed smart contract language, covering DeFi, NFTs, governance, bridges, and all Ethereum-ecosystem protocols.

Supported Chains

Chain	EVM Compatibility	Key Differences
Ethereum	Full	Baseline — all patterns apply
Arbitrum	Full	L2 sequencer risk, `block.number` returns L1 block, gas pricing differs
Optimism / Base	Full	L2 sequencer risk, `TIMESTAMP` from L1, cross-domain messaging
Polygon	Full	Different gas token (MATIC), PoS consensus, reorg risk higher
BSC	Full	Lower gas costs enable different attack economics
Avalanche	Full	Subnet awareness, different finality model
Scroll	Full	zkEVM — some precompile differences
Linea	Full	zkEVM — some opcode cost differences
zkSync Era	Partial	Different address derivation, no `SELFDESTRUCT`, custom deployment model
Blast	Full	Native yield — `WETH.balance()` increases, rebasing assumptions

Chain-Specific Audit Considerations

When auditing for a specific chain, check these additional concerns:

Arbitrum/Optimism:
  ├── Sequencer downtime → oracle stale price risk
  ├── L1-to-L2 message delay → bridge timing attacks
  └── block.number semantics differ from L1

zkSync Era:
  ├── msg.value behaves differently in system contracts
  ├── Contract deployment uses CREATE2-like hash, not CREATE
  ├── Some opcodes unavailable or priced differently
  └── Native account abstraction changes tx.origin semantics

Blast:
  ├── ETH and USDB are rebasing tokens by default
  ├── Protocol must explicitly configure yield mode
  └── balanceOf(address) can change between transactions without transfers

Detection Capabilities

Critical / High Severity

Category	Specific Patterns	Detection Method
Reentrancy	Classic single-function, cross-function, cross-contract, read-only, ERC777 callback, ERC721 callback	State write after external call analysis
Access control	Missing modifiers, `tx.origin` auth, unprotected `initialize()`, unprotected `selfdestruct`, privilege escalation	Public/external function modifier scan
Unsafe external calls	Unchecked `transfer()` return, unchecked low-level call, unchecked `approve()`, USDT non-standard behavior	Return value tracking
Oracle manipulation	Uniswap V2/V3 spot price, missing Chainlink staleness check, reserve-based pricing, circular pricing	Oracle usage pattern matching
Flash loan vectors	Balance-based pricing, single-tx manipulation, donation attacks	Balance-as-input detection
Proxy vulnerabilities	Uninitialized impl, storage collision, missing `_disableInitializers()`, UUPS auth bypass	Proxy pattern recognition

Medium Severity

Category	Specific Patterns	Detection Method
Integer issues	Unsafe downcast, truncation on assignment, rounding errors in share math, first depositor inflation	`SafeCast` absence, division analysis
Token handling	Fee-on-transfer incompatibility, rebasing token assumption, non-standard decimals, approve race condition	Token interaction pattern scan
MEV exposure	Missing deadline, missing slippage protection, sandwich vulnerability, permit front-running	Swap/router call analysis
Centralization	Untimelocked admin powers, excessive owner privileges, upgradeable without governance	Admin function audit
Signature issues	Missing nonce, missing chainId, missing deadline, ecrecover zero-address, malleable signatures	Signature verification scan
DoS vectors	Unbounded loops, external call revert in batch, force-sent ETH breaking balance checks	Loop and batch analysis

Low / Informational

Category	Specific Patterns
Gas optimization	Storage vs memory, redundant SLOADs, unchecked math for bounded loops, calldata vs memory
Code quality	Missing events, missing NatSpec, unused variables, floating pragma, unlocked compiler
Best practices	`block.timestamp` dependency, missing zero-address checks, magic numbers, missing error messages

Compiler Version Awareness

Solidity Version	Key Security Considerations
< 0.8.0	No built-in overflow protection — check for SafeMath usage
0.8.0–0.8.12	Built-in overflow but `unchecked` blocks bypass it — audit all `unchecked` usage
0.8.13–0.8.14	ABI encoder bug with nested arrays (fixed in 0.8.15)
0.8.15–0.8.19	Optimizer bug with `Yul` code (fixed in 0.8.20)
0.8.20+	Default EVM target = Shanghai (`PUSH0`) — may not deploy on all L2s
0.8.24+	Transient storage (`TSTORE`/`TLOAD`) available — new reentrancy guard patterns
0.8.26+	Custom storage layouts, event errors in interfaces

Workflows

Workflow	Duration	Best For	Link
Quick Scan	15–20 min	Triage, contest warm-up, initial assessment	quick-scan.md
Comprehensive Audit	3–5 days	Protocol launch, client engagement, major upgrade	comprehensive-audit.md
Competitive Audit	8–16 hours	Code4rena, Sherlock, CodeHawks contests	competitive-audit.md

Resources

Resource	Purpose	Link
Vulnerability Patterns	Complete pattern catalog with code examples	vulnerability-patterns.md
Severity Guide	Classification criteria with decision tree	severity-guide.md
Tool Configs	Slither, Aderyn, Mythril, Semgrep setup	tool-configs.md
False Positives	Common FPs with reasoning for each	false-positives.md
Foundry Security	10 vulnerability categories with Foundry PoC tests	foundry-security.md
Foundry Testing	Fuzz, invariant, fork, differential testing guide	foundry-testing.md
Foundry Cheatcodes	150+ cheatcodes reference for security auditors	foundry-cheatcodes.md
Gas & Security	Gas optimization patterns with security trade-offs	gas-security.md
Foundry CI/CD	GitHub Actions for automated security testing	foundry-ci-cd.md

Standard Audit Procedure

1. Load Solidity contract(s) and note compiler version
2. Map inheritance tree and external dependencies
3. Identify protocol type (DeFi, NFT, governance, bridge, etc.)
4. Select workflow based on engagement type
5. Run static analysis tools (Slither → Aderyn → Mythril)
6. Execute manual review per methodology
7. Classify each finding with severity guide
8. Run variant analysis on confirmed findings
9. Generate structured report

Integration with Other Skills

Skill	How Solidity Scanner Uses It
`methodology/`	Provides the audit methodology framework (phases, timing, approach)
`severity/`	Classifies each finding into Critical/High/Medium/Low
`scoring/`	Scores overall protocol security posture
`checklists/`	Protocol-specific security checklists (ERC-20, vault, AMM, etc.)
`patterns/`	Vulnerability pattern database for cross-reference
`variant-analysis/`	When one bug is found, hunt for all variants
`static-analysis/`	Tool configuration and integration
`exploit-forensics/`	Real-world exploit case studies for pattern awareness
`fix-review/`	Verify proposed fixes after initial audit
`differential-review/`	Compare upgraded contract versions
`chain-guides/`	Chain-specific considerations when target != Ethereum mainnet

Error Code Reference

Common Solidity/EVM error selectors and revert reasons encountered during audits. Use a selector decoder like openchain.xyz or 4byte.directory to identify unknown selectors.

OpenZeppelin Standard Errors

Error Selector	Error Signature	Meaning
`0xe450d38c`	`ERC20InsufficientBalance(address,uint256,uint256)`	Token balance too low for transfer
`0xfb8f41b2`	`ERC20InsufficientAllowance(address,uint256,uint256)`	Allowance too low for transferFrom
`0x118cdaa7`	`OwnableUnauthorizedAccount(address)`	Caller is not the owner
`0x1e4fbdf7`	`OwnableInvalidOwner(address)`	Invalid owner address (e.g., zero address)
`0xe602df05`	`ERC20InvalidApprover(address)`	Invalid address for approve
`0x94280d62`	`ERC20InvalidReceiver(address)`	Invalid receiver (zero address)
`0xd93c0665`	`EnforcedPause()`	Contract is paused
`0x8dfc202b`	`ExpectedPause()`	Contract is NOT paused (expected to be)
`0xa9fbf51f`	`AccessControlUnauthorizedAccount(address,bytes32)`	Missing role for access control
`0xd92e233d`	`ZeroAddress()`	Zero address provided where not allowed

ERC Standard Errors

Error Selector	Error Signature	Meaning
`0x7e273289`	`ERC721NonexistentToken(uint256)`	Token ID does not exist
`0x177e802f`	`ERC721InsufficientApproval(address,uint256)`	Not approved for token operation
`0x64283d7b`	`ERC721IncorrectOwner(address,uint256,address)`	Token not owned by expected address
`0xf0dd15fd`	`ERC4626ExceededMaxDeposit(address,uint256,uint256)`	Deposit exceeds vault max
`0x936941fc`	`ERC4626ExceededMaxRedeem(address,uint256,uint256)`	Redeem exceeds vault max

Common Revert Reasons (String)

Revert String	Typical Source	Audit Significance
`"ReentrancyGuard: reentrant call"`	OpenZeppelin ReentrancyGuard	Guard is active — check if all entry points are protected
`"Initializable: contract is already initialized"`	OZ proxy initializer	Re-initialization attempt — check `_disableInitializers()`
`"Address: low-level call failed"`	OZ Address library	External call failure — check error handling
`"SafeERC20: low-level call failed"`	OZ SafeERC20	Token transfer failure — may indicate non-standard token
`"Pausable: paused"` / `"Pausable: not paused"`	OZ Pausable	Pause state mismatch — check centralization risk
`"ECDSA: invalid signature"`	OZ ECDSA	Signature verification failed — check for malleable sigs
`"ERC20: transfer amount exceeds balance"`	OZ ERC20 (pre-custom-errors)	Insufficient balance — older OZ version indicator

Proxy-Related Errors

Error Selector	Error Signature	Meaning
`0xb398979f`	`ERC1967InvalidImplementation(address)`	Invalid implementation address for proxy
`0x4c9c8ce3`	`ERC1967InvalidAdmin(address)`	Invalid admin address for transparent proxy
`0x7e2732890`	`ERC1967NonPayable()`	Proxy received ETH when not expected
`0xf92ee8a9`	`InvalidInitialization()`	OZ v5 Initializable — already initialized
`0xd7e6bcf8`	`NotInitializing()`	OZ v5 Initializable — not in initializing state

Troubleshooting

Issue	Likely Cause	Solution
Scanner loads generic patterns instead of Solidity-specific	Trigger phrases not matching the Solidity scanner	Verify `triggers` field in frontmatter matches user query; check TRIGGERS.md mapping
False positives on `unchecked` blocks	Scanner flags all unchecked math as unsafe	Check Solidity version — 0.8.x+ has built-in overflow; `unchecked` in bounded loops is safe
Missed reentrancy in cross-contract calls	Scanner only checks single-function reentrancy	Enable cross-contract analysis mode; load `patterns/` for read-only reentrancy patterns
Oracle manipulation not detected	Protocol uses custom oracle not matching known patterns	Manually check any `balanceOf()` or reserve-based pricing; add custom oracle pattern
L2-specific issues not flagged	Chain-specific guide not loaded	Load the appropriate `chain-guides/` file for the target L2 before scanning
Proxy storage collision missed	Scanner doesn't map storage layouts across proxy/impl	Use `differential-review/` skill to compare storage layouts; check for `_gap` variables
Too many low-severity findings	Scanning in paranoid mode	Switch to "Standard" scan profile; filter informational findings for final report

Solidity Scanner

File contents

Solidity Scanner Skill

Purpose

Supported Chains

Chain-Specific Audit Considerations

Detection Capabilities

Critical / High Severity

Medium Severity

Low / Informational

Compiler Version Awareness

Workflows

Resources

Standard Audit Procedure

Integration with Other Skills

Error Code Reference

OpenZeppelin Standard Errors

ERC Standard Errors

Common Revert Reasons (String)

Proxy-Related Errors

Troubleshooting

Frequently asked questions

Solidity Scanner

File contents

Solidity Scanner Skill

Purpose

Supported Chains

Chain-Specific Audit Considerations

Detection Capabilities

Critical / High Severity

Medium Severity

Low / Informational

Compiler Version Awareness

Workflows

Resources

Standard Audit Procedure

Integration with Other Skills

Error Code Reference

OpenZeppelin Standard Errors

ERC Standard Errors

Common Revert Reasons (String)

Proxy-Related Errors

Troubleshooting

Related skills

Frequently asked questions

How do I install the Solidity Scanner skill?

What does the Solidity Scanner skill do?

Is Solidity Scanner safe to use?

Which AI agents work with Solidity Scanner?

Is Solidity Scanner free to use?

Who published Solidity Scanner?