token-approval-safety SKILL.md skillA
token-approval-safety from nirholas/three.ws is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add nirholas/three.ws/token-approval-safety@git:20260501.87cefc9Pins git:20260501.87cefc9 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- nirholas/three.ws
- Path
data/skills/security/token-approval-safety/SKILL.md- Versions recorded
- 1
- Latest version
- git:20260501.87cefc9, committed May 1, 2026
- Size
- 5,196 bytes
- Repository stars
- 269
- License
- Apache-2.0
Guide to ERC-20 token approvals — how they work, why unlimited approvals are risky, how to check and revoke approvals, and best practices. Use when helping users manage approvals, audit wallet security, or understand approval-related risks.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Token Approval Safety Guide Token approvals are one of the most overlooked security risks in DeFi. This guide helps AI agents protect users from approval-related attacks. ## How Approvals Work When you interact with a DeFi protocol, you must first "approve" it to spend your tokens: ``` 1. You call approve(spenderAddress, amount) on the token contract 2. The spender (DEX, protocol) can now transfer up to `amount` of your tokens 3. When you swap/deposit, the protocol calls transferFrom() to move your tokens ``` ### The Problem: Unlimited Approvals Most DeFi UIs request **unlimited approval** (`type(uint256).max`): - Saves gas on future interactions (no re-approval needed) - But: the protocol can spend ALL your tokens FOREVER - If the protocol gets hacked, attackers drain your tokens via the approval ## Risk Levels | Approval Type | Risk | When to Use | |--------------|------|-------------| | Exact amount | Low | Large deposits, untrusted protocols | | Limited amount | Medium | Regular use with trusted protocols | | Unlimited | High | Only with battle-tested protocols (Uniswap, Aave) | | Permit (EIP-2612) | Medium | Gasless approvals, common in modern DeFi | …
Read the whole file at its exact version.
How to install
mdr add nirholas/three.ws/token-approval-safety@sha256:55a909053cc48ce5The line at the top of this page pins the label git:20260501.87cefc9, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_rcwqxlyw5cifsevg)
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Versions
The registry has recorded 1 version of this file, committed on May 1, 2026.
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (5196 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
nirholas/three.ws · 269 stars · license Apache-2.0 · pushed 2026-11-06 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_rcwqxlyw5cifsevg GET https://markdownregistry.com/api/v1/resolve?ref=nirholas/three.ws/token-approval-safety GET https://markdownregistry.com/api/v1/blob/55a909053cc48ce5603d6ffdd528b8320cda4e78df909c52d6fbe88edc91f79a
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.