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# Hooks, PCI Compliance, and Blocking Messages

1. **Introduction of `Hook`s in Workflows**: You can now use [`Hooks`](https://api.vapi.ai/api#:~:text=Hook) in your workflows to automatically execute actions when specific events occur, like task start or confirmation. Hooks are now available in [`ApiRequest`](https://api.vapi.ai/api#:~:text=ApiRequest) and [`Gather`](https://api.vapi.ai/api#:~:text=Gather) workflow nodes.

2. **Make your Assistant PCI Compliant**: You can now configure [`Assistant.pciEnabled`](https://api.vapi.ai/api#:~:text=UpdateCallDTO-,Assistant,-UpdateAssistantDTO) to indicate if your assistant deals with sensitive cardholder data that requires PCI compliance, helping you meet security standards for financial information.

3. **Blocking Messages before Tool Calls**: You can now configure your tool calls to wait until a message is fully spoken before starting with [`ToolMessageStart.blocking=true`](https://api.vapi.ai/api#:~:text=ToolMessageStart) (default is `false`).