sensitive-blue•4mo ago

Multiple Issues with vapi MCP client on web sdk:

I am trying to connect zapier mcp to vapi the agent works perfect i have followed the docs from each side accurately and tested multiple times but it doesn't work and the same error occurs (call.in-progress.error-vapifault-azure-openai-llm-failed) everytime: example of a failed call: 0ddd16af-08e9-4e4f-8f1d-eadd057cffd5 3f3c7722-67db-4de6-ad65-40a32ea464c3 example of working call: 508a4fda-b3c1-4e23-a6bc-651d1cc6b0d4 I have an action attached to zapier which should tell me the names of the users on slack using vapi mcp client but when the call is connected it plays the background noises(office noises) ... but nothing is generated via the LLM and the call disconnects. One more thing i'd like to point out is the docs are incorrect in a couple of places: 1. zapier has deprecated sse and this url mentioned here: https://docs.vapi.ai/tools/mcp#1-obtain-mcp-server-url and they've migrated to this url: https://mcp.zapier.app/home 2. the mcp object doesn't take a name in the request or either the types in web sdk are incorrect: https://docs.vapi.ai/tools/mcp#example-usage

Model Context Protocol (MCP) Integration | Vapi

Connect your assistant to dynamic tools through MCP servers for enhanced capabilities.

16 Replies

Vapi Support Bot•4mo ago

Thank you for the detailed report. To help narrow down the issue: Does your Slack user-fetching action work correctly when triggered directly from Zapier (outside of Vapi MCP), or does the failure only occur when the action is invoked via the Vapi MCP integration? This will help determine if the problem is with the integration or the underlying action. Let me know, and I can suggest the next steps! Source: - Vapi MCP Tool Documentation

⤵️ Mention @Vapi Support Bot for follow-ups 🐥

sensitive-blueOP•4mo ago

using directly from zapier works... and this is not just the slack action... others aren't working too. the issue is not with slack but rather vapi client conflicting with the mcp tools + without as any the type wont accept "mcp" my vapi version is "@Vapi-ai/server-sdk": "^0.8.1"

Vapi Support Bot•4mo ago

Thank you for the detailed information. To help pinpoint the issue: Are you able to successfully invoke any MCP tool action (even a simple one) via the Vapi MCP integration with your current @Vapi-ai/server-sdk (^0.8.1) setup, or do all MCP tool actions fail with the same LLM error? This will clarify if the problem is with the general MCP integration or specific to certain actions. Let me know, and I can suggest targeted next steps! Sources: - Vapi Call End Reasons - Vapi MCP Tool Documentation Thank you for the detailed information. To help pinpoint the issue, could you please confirm whether you have tried including a "name" field in your mcpTool object (as shown in the example usage), and if so, did it change the behavior or error message in your integration with @Vapi-ai/server-sdk version ^0.8.1? Example:

const mcpTool = {
  type: 'mcp',
  name: 'mcpTools', // try including this field
  server: { url: action.serverUrl }
};

const mcpTool = {
  type: 'mcp',
  name: 'mcpTools', // try including this field
  server: { url: action.serverUrl }
};

This will help determine if the missing "name" field is causing the SDK to reject the tool configuration. Source: - Vapi MCP Tool Documentation

sensitive-blueOP•4mo ago

including the name results in this error:

"message": [
    "model.each value in tools.property name should not exist"
  ],
  "error": "Bad Request",
  "statusCode": 400

"message": [
    "model.each value in tools.property name should not exist"
  ],
  "error": "Bad Request",
  "statusCode": 400

Vapi Support Bot•4mo ago

Thank you for the detailed information and error logs. Based on your experience and the documentation, there appears to be a mismatch between the documented MCP tool configuration and what the @Vapi-ai/server-sdk (^0.8.1) actually accepts. Could you please confirm if you have tried configuring your MCP tool without the name field, using only:

const mcpTool = {
  type: 'mcp',
  server: { url: action.serverUrl }
};

const mcpTool = {
  type: 'mcp',
  server: { url: action.serverUrl }
};

If so, does this configuration still result in the call.in-progress.error-vapifault-azure-openai-llm-failed error, or does it change the behavior? This will help determine if the issue is strictly with the tool configuration or if there is a deeper integration problem. For reference: Vapi MCP Tool Documentation Sources: - Vapi MCP Tool Documentation - Vapi Call End Reasons

sensitive-blueOP•4mo ago

can you give me an example of a simple action ? and how to set mcp tool up using code

Vapi Support Bot•4mo ago

It appears that the @Vapi-ai/server-sdk (^0.8.1) does not accept a name property in the MCP tool configuration, even though the documentation shows it. Try defining your MCP tool like this (without the name field):

const mcpTool = {
  type: 'mcp',
  server: { url: action.serverUrl }
};

const mcpTool = {
  type: 'mcp',
  server: { url: action.serverUrl }
};

Remove the name property and see if this resolves the validation error. If the issue persists, consider checking for SDK updates or reporting the documentation mismatch to Vapi support for clarification. Source: Vapi MCP Tool Documentation Source: - Vapi MCP Tool Documentation

sensitive-blueOP•4mo ago

removing the name does solve the error but the type:'mcp' not expected still is there.

Vapi Support Bot•4mo ago

To set up a simple MCP tool action in your assistant configuration, use the following code (without a name property):

const mcpTool = {
  type: 'mcp',
  server: { url: 'https://mcp.zapier.app/home' } // Replace with your actual MCP server URL
};

const mcpTool = {
  type: 'mcp',
  server: { url: 'https://mcp.zapier.app/home' } // Replace with your actual MCP server URL
};

Add this mcpTool to your assistant's tools array. This matches what the @Vapi-ai/server-sdk (^0.8.1) expects and should avoid validation errors.
Reference: Vapi MCP Tool Documentation Source: - Vapi MCP Tool Documentation To set up an MCP tool in your code with @Vapi-ai/server-sdk (^0.8.1), use the following structure (without the name property):

const mcpTool = {
  type: 'mcp',
  server: { url: action.serverUrl }
};

const mcpTool = {
  type: 'mcp',
  server: { url: action.serverUrl }
};

If you still see a "type: 'mcp' not expected" error, it may indicate a version mismatch or SDK limitation. Consider checking for SDK updates or reporting this to Vapi support for clarification, as the documentation and SDK may be out of sync. Source: Vapi MCP Tool Documentation Source: - Vapi MCP Tool Documentation To set up an MCP tool in your code, use the following configuration (without a name property):

const mcpTool = {
  type: 'mcp',
  server: { url: action.serverUrl }
};

const mcpTool = {
  type: 'mcp',
  server: { url: action.serverUrl }
};

If you still see a "type: 'mcp' not expected" error, this may indicate a mismatch between the SDK and the documentation. In that case, check for SDK updates or report the issue to Vapi support for clarification, as the documentation does not specify an alternative type value for MCP tools in your SDK version. Source: Vapi MCP Tool Documentation Source: - Vapi MCP Tool Documentation

sensitive-blueOP•4mo ago

@Duckie pls ping when someone from vapi support or engineering team is here.

Vapi Support Bot•4mo ago

Here’s a simple example of how to set up an MCP tool in your assistant’s configuration using @Vapi-ai/server-sdk (^0.8.1):

const mcpTool = {
  type: 'mcp',
  server: { url: 'https://your-mcp-server-url' } // Replace with your actual MCP server URL
};

const mcpTool = {
  type: 'mcp',
  server: { url: 'https://your-mcp-server-url' } // Replace with your actual MCP server URL
};

Add this object to your assistant’s tools array. If you still see a "type: 'mcp' not expected" error, it may be an SDK limitation—please check for updates or contact Vapi support for further help.
Source: Vapi MCP Tool Documentation Source: - Vapi MCP Tool Documentation There is no built-in way to "ping" or directly notify a Vapi support or engineering team member from within the platform.
For the fastest response, please email support@vapi.ai or post your request in the Vapi Discord #support channel.
This is the recommended method to get direct attention from the Vapi team. Source: - Vapi Support Documentation

sensitive-blueOP•4mo ago

the latest call id which failed: 559fa28f-4291-449c-a003-b66b0cf09f39

Vapi Support Bot•4mo ago

Here’s a simple example of how to set up an MCP tool in your assistant’s configuration:

const mcpTool = {
  type: 'mcp',
  server: { url: 'https://your-mcp-server-url' } // Replace with your actual MCP server URL
};

const mcpTool = {
  type: 'mcp',
  server: { url: 'https://your-mcp-server-url' } // Replace with your actual MCP server URL
};

Add this object to your assistant’s tools array. If you still see a "type: 'mcp' not expected" error, check for SDK updates or contact Vapi support for further help.
Reference: Vapi MCP Tool Documentation Source: - Vapi MCP Tool Documentation Here's a simple example of setting up an MCP tool in your assistant's configuration:

const mcpTool = {
  type: 'mcp',
  server: { url: 'https://your-mcp-server-url' } // Replace with your actual MCP server URL
};

const mcpTool = {
  type: 'mcp',
  server: { url: 'https://your-mcp-server-url' } // Replace with your actual MCP server URL
};

Add this object to your assistant's tools array. If you still see a "type: 'mcp' not expected" error, check for SDK updates or contact Vapi support, as this may be a version mismatch.
Reference: Vapi MCP Tool Documentation Source: - Vapi MCP Tool Documentation

fascinating-indigo•4mo ago

Looking into it

Vapi Support Bot•4mo ago

To have your failed call (ID: 559fa28f-4291-449c-a003-b66b0cf09f39) investigated, please email support@vapi.ai with your call ID and account email, or post the details in the Vapi Discord #support channel.
This is the recommended way to get direct attention from the Vapi support and engineering team for call failures. Sources: - Vapi Call Ended Reasons Documentation - Vapi Support Documentation To have your failed call (ID: 559fa28f-4291-449c-a003-b66b0cf09f39) investigated, please email support@vapi.ai with your call ID and account email, or post the details in the Vapi Discord #support channel.
This is the recommended way to get direct attention from the Vapi support and engineering team for call failures. Sources: - Vapi Call Ended Reasons Documentation - Vapi Support Documentation

Sahil•4mo ago

🔵 04:17:38:402 Couldn't Complete Model Sequence. Request Failed And Sequence Empty (provider: azure-openai, model: gpt-4o-2024-08-06, region: eastus2, credential: false) (Invalid 'tools[1].function.name': empty string. Expected a string with minimum length 1, but got an empty string instead.)

Looks like MCP server that you created contains a tool name which is empty.

Multiple Issues with vapi MCP client on web sdk:

Did you find this page helpful?