# Overview Before you start building with the Nodefy API, it's helpful to understand the following core concepts: ### Webhooks Webhooks are triggered when certain onchain events occur on the blockchain networks you're monitoring. These events could include: * Token transfers * Smart contract function calls * NFT minting or sales * ...and more Nodefy lets you create webhooks to listen for these events, and when a webhook is triggered, it sends a notification to your users through the channels you have configured. ### Filters Filters allow you to refine the conditions under which a webhook is triggered. You can specify criteria such as: * Token type * Transaction value * Specific addresses or contract functions By applying filters, you can ensure that notifications are only sent for the events that are truly relevant to your users. ### Actions Actions are the steps taken when a webhook is triggered and its associated filters are met. Nodefy offers a variety of built-in actions, including: * Sending email notifications * Sending Telegram messages * Posting to Slack channels * Calling custom webhooks (for more flexibility building event-driven systems) You can configure different actions for different webhooks, allowing you to tailor the notification experience to your specific needs. --- # Agent Instructions: 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: ``` GET https://docs.nodefy.xyz/our-api-guide/overview.md?ask= ``` The question should be specific, self-contained, and written in natural language. 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.