Token Approval
A token approval grants a contract permission to move your tokens — persistent, often unlimited, and the most common source of avoidable losses.
/ quick answer
ERC-20 style tokens require an allowance before a contract can transfer them. Wallets default to large or unlimited allowances for convenience, so a later exploit or a malicious contract you approved months ago can still drain that token. Periodic approval review and revocation is basic hygiene for any active wallet.
/ frequently asked
What is Token Approval?
ERC-20 style tokens require an allowance before a contract can transfer them. Wallets default to large or unlimited allowances for convenience, so a later exploit or a malicious contract you approved months ago can still drain that token. Periodic approval review and revocation is basic hygiene for any active wallet.
What is an example of Token Approval?
Revoking an unlimited approval to a DEX router you last used a year ago, before a proxy upgrade turns it into a liability.
Why does Token Approval matter?
A token approval grants a contract permission to move your tokens — persistent, often unlimited, and the most common source of avoidable losses.
What should I learn after Token Approval?
Open the related workflows and prompts further down this page: they show how this idea is applied in a real task, step by step.
/ continue exploring
Related concepts
The vocabulary this page depends on.
- →Web3 Wallet
A Web3 wallet stores your keys and signs transactions, letting you hold assets and connect to on-chain applications without an intermediary.
- →Self-Custody
Self-custody means you control the private keys to your assets, so no company can freeze, lend out or lose them on your behalf.
- →Seed Phrase
A seed phrase is the 12–24 word backup from which every private key in a wallet is derived — whoever holds it holds the wallet.
- →Private Key
A private key is the secret number that authorises transactions from an address; the public address is derived from it, never the reverse.
Related workflows
Turn this into a repeatable process.
- →AI Crypto Research Workflow
A repeatable research loop: turn a question into market data, on-chain evidence and a written risk view before any position is considered.
- →DEX Trading Workflow
Execute an on-chain swap deliberately: research, liquidity check, route comparison, sized order, then position monitoring.
- →Automate Repetitive Web3 Actions
Replace manual claims, approvals and rebalances with scoped automations that cannot spend more than you allowed.
- →Audit MCP Tool Security
A checklist that catches the failure modes unique to model-driven tool calls.
Related tool stacks
The tools that run it in production.
- →AI Security Stack
Least-privilege tooling, approval gates and audit trails for agentic systems.
- →AI Agent + Web3 Stack
Agent framework, MCP/API tools, blockchain data access and a limited signing layer — with policy enforced in code.
Related prompts
Reusable prompts for this job.
- →Transaction Analysis Prompt
Explains what a specific transaction did, what it authorised, and what risk it left behind.
- →Refactor and Security Review Prompt
Clean up a vibe-coded app and catch security gaps before launch.
- →Autonomy Boundary Prompt
Defines exactly what an agent may do alone, with approval, or never.
Related use cases
How people apply it, and what came out.
- →Use DeFi With A Web3 Wallet
A first-time DeFi user moved from an exchange to self-custody with a test-transfer routine and a 2% allocation cap, avoiding two protocol failures.
- →Monitor Wallet Transactions
Alerting on the user's own wallet activity caught an unauthorised approval attempt and forced an approval cleanup that removed 14 standing allowances.
- →Automate Repetitive Web3 Actions
Automating reward claims and gas top-ups with session keys and spend caps saved about 5 hours per month with no unbounded authority.
Comparisons & alternatives
Pick between the options.
- →Hot Wallet vs Cold Wallet
Hot wallets trade convenience for exposure; cold wallets trade friction for a signing key that never touches an internet-connected device.
- →Rabby vs OKX Web3 Wallet
Rabby is the safety-focused EVM wallet with pre-transaction simulation; OKX Web3 Wallet trades some of that depth for multi-chain breadth and built-in trading.
- →MetaMask vs OKX Web3 Wallet
MetaMask is the EVM default with the widest DApp support; OKX Web3 Wallet bundles multi-chain coverage, a DEX aggregator and exchange integration in one app.
- →Phantom vs OKX Web3 Wallet
Phantom is a Solana-first wallet with best-in-class UX on that ecosystem; OKX Web3 Wallet is a generalist multi-chain wallet for users spread across networks.