The takeaway
Check what you are authorising, who can spend and how much. Connection, signatures, approvals and transfers are different actions.
Separate connection from permission
Connecting a wallet lets an application see the account you choose to share; it does not automatically authorise every token transfer. An ERC-20 approval is a separate permission that allows a specified spender to use tokens up to an allowance. A swap may therefore involve more than one request. Read each request on its own terms instead of treating a sequence of wallet prompts as one harmless sign-in. The token, spender and network all matter.
Understand the amount at risk
An allowance can be larger than the transaction you intend to make. A very broad allowance reduces repeated prompts but increases the amount a permitted spender could access if something goes wrong. Check the exact token contract and spender against the application’s official documentation. A familiar display name is not sufficient. Some permissions use signed messages rather than an immediate transaction; a prompt without a gas fee can still grant consequential authority. If the request is unclear, decline it.
Review permissions after using an app
Closing the website or disconnecting the wallet does not necessarily change permissions already recorded on-chain. Review allowances through a trusted wallet or explorer, and confirm any revocation on the correct network. Revoking an allowance may require a network transaction and a fee; it cannot undo a transfer that already happened. These checks apply when you control the signing wallet. An address assigned by a service does not itself give you the private-key access needed to manage that address’s allowances.
Sources & further reading
- Ethereum Improvement Proposals — ERC-20 Token Standardeips.ethereum.org
- MetaMask — Revoking token approvalssupport.metamask.io
- Uniswap Labs — Approval transactionssupport.uniswap.org
Original educational content. Not personal investment advice, live market research or a recommendation to buy. Sources inform the explanation; they do not endorse SafeCoin.