> For the complete documentation index, see [llms.txt](https://docs.onto.app/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.onto.app/basics/assets-management/approve.md). # Approve When using a smart contract, such as swapping a token, users usually need to approve that the smart contract is allowed to spend that token in their address. This is because non-native tokens, such as ERC-20 tokens, are smart contracts themselves, therefore they cannot be sent directly to a smart contract and call its functions. **Approve amount** is the cumulative amount that a certain smart contract is allowed to spend a certain token of a certain address. When using swap or bridge functions on ONTO's "Market" page, users can choose between two types of approve amount: **suggested amount** or **unlimited amount**. * **Suggested amount**: the required amount of this transaction. This means that users need to approve this token again the next time they perform transactions with this smart contract. * **Unlimited amount**: the maximum amount of this data type, of which the effect is equivalent to unlimited. This means that users don't need to approve again in the future when performing transactions of this token with this smart contract, but are exposed to a higher risk of token loss when there are hacks or bugs in this smart contract. In general, **suggested amount** is **more secure**, while **unlimited amount** is more **convenient** and has **lower fees**. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.onto.app/basics/assets-management/approve.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.