VAPI•7mo ago

Mcp issue

Need help.

Set up an MCP server in n8n. All Google Calendar nodes are connected — create, get, update, delete. OAuth is working.

But the assistant keeps throwing errors like:

“I encountered an issue accessing the calendar tool. Let me try again…”

Tool is named mcp_tool.
Chat ID: fc8fb499-c5d7-451a-b6d4-4bd1c619c4f5

If anyone can check or suggest what’s missing, I need this fixed ASAP.

Thanks.

worthy-rose•6/11/25, 8:54 AM

I'm encountering the same issue: I've tried different Zapier MCPs, and while the connection works via Postman, it fails when using Vapi and returns an error.

worthy-rose•6/11/25, 9:11 AM

call id - 56f62483-bfcf-4348-b93c-97b16b63e89b

efficient-indigoOP•6/11/25, 9:22 AM

any updates ? @Vapi Team

extreme-purple•6/11/25, 9:23 AM

Looking into it

efficient-indigoOP•6/11/25, 9:34 AM

I am able to test the tool properly still, facing issues while using it, I think the agent doesnt trigger it.

efficient-indigoOP•6/11/25, 9:58 AM

@Kings_big

what's the update

efficient-indigoOP•6/11/25, 10:11 AM

@Vapi Team

efficient-indigoOP•6/11/25, 10:34 AM

@Shubham Bajaj

dramatic-maroon•6/11/25, 10:34 AM

@Vapi Team still waiting for the fix, what’s the ETA for this ?

efficient-indigoOP•6/11/25, 6:09 PM

@Vapi Team

efficient-indigoOP•6/11/25, 6:09 PM

Any updates would be helpful

efficient-indigoOP•6/11/25, 7:17 PM

@Kings_big

efficient-indigoOP•6/11/25, 7:17 PM

@Arvind

efficient-indigoOP•6/11/25, 7:18 PM

@Shubham Bajaj

efficient-indigoOP•6/11/25, 8:15 PM

cmon guys, have to use Retell ai now

efficient-indigoOP•6/11/25, 8:15 PM

lol

efficient-indigoOP•6/11/25, 8:16 PM

@Vapi Team

dangerous-fuchsia•6/11/25, 10:06 PM

Hey @n0tmad @Joseph @mukul I am looking into this MCP issue.
cc: @Kings_big

dangerous-fuchsia•6/11/25, 10:29 PM

call_id: 56f62483-bfcf-4348-b93c-97b16b63e89b

logs

logs

15:08:02:679 [user ERROR] Tool mcp:Slack-Operationsmcp:Slack-Operations failed (reason: mcp server https://mcp.zapier.com/api/mcp/s/NmxjOQ==/mcp rejected request)

15:08:03:420 Conversation Buffer Appending Tool Result. Emitting "conversation-update"...
[
{
"role": "tool_call_result",
"time": 1749568083419,
"secondsFromStart": 43.238,
"name": "Slack-Operations",
"result": "{"error": "Failed to connect to MCP server"}",
"toolCallId": "call_kyqmtJLlwM9qEjrUBUC56yrm"
}
]

15:08:02:483 Converted Requested Tools Calls To Internal Format. [
{
"type": "mcp",
"server": {
"url": "https://mcp.zapier.com/api/mcp/s/NmU3xxxxdjOQ==/mcp",
"headers": {
"X-Call-Id": "56fxxxxx63e89b"
}
},
"messages": [],
"function": {
"name": "Slack-Operations",
"description": "Performs any slack opperation",
"parameters": {"type": "object", "properties": {}, "required": []}
},
"toolCall": {
"id": "call_kyqmxxxx56yrm",
"type": "function",
"function": {"name": "Slack-Operations", "arguments": {}}
}
}
]

As you can see from the call logs, your MCP server rejected the requests. It's not Vapi. Please check your mcp logs to understand why and what actions you can take to accept the REQUEST. I've attached the request we sent as well.

cc: @n0tmad @Kings_big

@Joseph @mukul

Eefficient-indigo Need help. Set up an MCP server in n8n. All Google Calendar nodes are connected...

dangerous-fuchsia•6/11/25, 10:47 PM

@n0tmadI reviewed the shared chat ID logs, but I couldn't make any definitive conclusions. Please provide a working call ID or chat ID example to compare them. Also, if you have more similars call IDs or chat IDs for your case, that would be helpful.

cc: @Kings_big

@Joseph @mukul

Ddangerous-fuchsia @n0tmadI reviewed the shared chat ID logs, but I couldn't make any definitive co...

efficient-indigoOP•6/12/25, 4:53 AM

0470b955-bbac-456b-babd-bd112a262059

This is the call id

dramatic-maroon•6/12/25, 9:40 AM

Hey @Shubham Bajaj so apparently the issue was because I've selected 'Streamable HTTP' for Transport Function, once I switched to SSE it worked

Curious to see what's the issue for @n0tmad using the n8n platform
cc: @mukul

Eefficient-indigo 0470b955-bbac-456b-babd-bd112a262059 This is the call id

dangerous-fuchsia•6/12/25, 5:15 PM

@n0tmad can you confirm if your transport config is set correctly?

Ddangerous-fuchsia @n0tmad can you confirm if your transport config is set correctly?

efficient-indigoOP•6/12/25, 10:41 PM

How can i check that?

efficient-indigoOP•6/12/25, 10:41 PM

i am using n8n and it uses SSE

efficient-indigoOP•6/13/25, 4:56 AM

efficient-indigoOP•6/13/25, 7:23 AM

@Shubham Bajaj

VapiAPP•6/13/25, 8:15 AM

Can you please make a call and provide us the latest call_id? We will take alook into it. If it doesn't work out will get on a quick call.

Ccomprehensive-tomato Can you please make a call and provide us the latest call_id? We will take alook...

efficient-indigoOP•6/13/25, 8:28 AM

1242aed9-0c8b-45b0-a42e-fbf3ee63845d

efficient-indigoOP•6/13/25, 8:28 AM

just made this call

efficient-indigoOP•6/13/25, 8:28 AM

please check

efficient-indigoOP•6/13/25, 9:07 AM

any updates guys?

efficient-indigoOP•6/13/25, 9:07 AM

@Vapi Team

efficient-indigoOP•6/13/25, 11:04 PM

@Vapi Team

efficient-indigoOP•6/14/25, 10:38 AM

Hey guys any fixes ? @Vapi Team

efficient-indigoOP•6/14/25, 10:38 AM

@Shubham Bajaj

efficient-indigoOP•6/14/25, 10:55 AM

@Kings_big

VapiAPP•6/14/25, 10:57 AM

Looking into it

efficient-indigoOP•6/14/25, 2:08 PM

@Kings_big

efficient-indigoOP•6/14/25, 2:08 PM

@Vapi Team

efficient-indigoOP•6/14/25, 2:23 PM

Any updates?

efficient-indigoOP•6/14/25, 2:23 PM

Its been 3 days already

efficient-indigoOP•6/15/25, 6:59 AM

@Vapi Team

efficient-indigoOP•6/15/25, 7:17 AM

I will keep on pinging till my error is solved

efficient-indigoOP•6/15/25, 7:17 AM

@Kings_big

whats the update?

efficient-indigoOP•6/15/25, 7:17 AM

did you check?

efficient-indigoOP•6/15/25, 7:18 AM

why the support system is so slow?

efficient-indigoOP•6/15/25, 7:19 AM

@Shubham Bajaj

Mcp issue

Similar Threads

Similar Threads

Similar Threads