My tool call (custom getAvailability and setMeeting) which gets sent to my server URL is coming back a success to the agent without finishing the workflow and the agent is giving back a success before Make.com even follows its workflow, can I get some help? This didn't happen before and also when I use the pre-built in tools the agent actually checks the schedule, but not with my custom tool. https://cdn.discordapp.com/attachments/1436938307941568514/1436938308231102484/Screenshot_2025-11-09_153820.png?ex=693c4555&is=693af3d5&hm=c6885724ba93dce7fad1e93e32b7ba0a03c5ca78c730f5d98cb66e6f96e4c7b0&

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Your custom tool is likely returning a success before your Make.com workflow finishes because it's set to async. To fix this, set

"async": false

in your tool configuration and ensure your webhook only returns a response after Make.com completes. Here’s a sample config:

json
{
  "name": "getAvailability",
  "async": false
}

Wait for your workflow to finish, then return the result in the required JSON format with HTTP 200. Source: - [Custom tools troubleshooting](https://docs.vapi.ai/tools/custom-tools-troubleshooting)

Message marked as helpful by @versin! 🎉

Hi versin, If you have a question about tool call errors or any other topic, feel free to share more details. I'm here to help.