Im having issues with MCP, I put in the webhook but no matter what it says error 500 when using SSE and it doesnt even let me use SHTTP. I tried using a N8N webhook and a Zapier webhook but none are working. Does anyone know the fix? https://cdn.discordapp.com/attachments/1417004919688400926/1417004920258691093/image.png?ex=68c8e82b&is=68c796ab&hm=d583d411c6bcbbea80f79e2c81933ba3f803c35d1766101f66e24675c5bed537& https://cdn.discordapp.com/attachments/1417004919688400926/1417004920875257948/image.png?ex=68c8e82b&is=68c796ab&hm=fa980823c3d5a293be36081c99e157208c4dce82e17bbb515c81d86bdc8d2050&

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I can help you fix the 500 error with your MCP setup. Usually, this happens if the webhook isn’t returning a valid JSON response or if SSE isn’t supported by the endpoint. I’ll go through your config step by step, test the payload, and set it up properly with Zapier or n8n so it works with SHTTP. Can you share the exact payload you’re sending and the type of trigger/action you want it to fire?

Also, if you would like to make a test, we would suggest testing a payload from outside of Vapi with some similar app like

postman

for testing request payloads then mimicking the structure that Vapi would send.

DMS

Alright I will check my dm now and reply to you immediately @Catman