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MCP Client

Use MCP client

Overview

This node acts as a client for the Model Context Protocol (MCP) server, enabling interaction with MCP resources, tools, and prompts. It supports multiple connection types (Command Line STDIO, Server-Sent Events, HTTP Streamable) to communicate with the MCP server. Common use cases include listing available resources, resource templates, tools, and prompts; reading specific resources by URI; executing tools with parameters; and retrieving prompt templates. This node is beneficial for workflows that require dynamic access to MCP-managed data and tool execution within an automation environment.

Use Case Examples

  1. List all available resources from the MCP server to dynamically populate options in a workflow.
  2. Execute a specific tool on the MCP server with JSON parameters and use the result in subsequent workflow steps.
  3. Retrieve a prompt template by name to customize user interactions or automated responses.

Properties

Name Meaning
Connection Type Selects the transport protocol to connect to the MCP server, such as Command Line (STDIO), Server-Sent Events (deprecated), or HTTP Streamable.
Operation Specifies the action to perform on the MCP server, such as listing resources, executing tools, or retrieving prompts.
Resource URI URI of the resource to read (used only with Read Resource operation).
Tool Name Name of the tool to execute (used only with Execute Tool operation).
Tool Parameters JSON-formatted parameters to pass to the tool (used only with Execute Tool operation).
Prompt Name Name of the prompt template to retrieve (used only with Get Prompt operation).

Output

JSON

  • resources - Array of available resources returned by the List Resources operation.
  • resourceTemplates - Array of available resource templates returned by the List Resource Templates operation.
  • resource - Details of a specific resource returned by the Read Resource operation.
  • tools - Array of available tools with their name, description, and input schema returned by the List Tools operation.
  • result - Result of executing a specific tool with given parameters returned by the Execute Tool operation.
  • prompts - Array of available prompt templates returned by the List Prompts operation.
  • prompt - Details of a specific prompt template returned by the Get Prompt operation.

Dependencies

  • Requires credentials for MCP client connection depending on the selected connection type: an API key or authentication token for HTTP Streamable or SSE, or command line access credentials for STDIO.

Troubleshooting

  • Connection errors may occur if the MCP server is unreachable or credentials are invalid; verify connection parameters and credentials.
  • Tool execution errors can happen if the tool name does not exist or parameters are invalid JSON; ensure the tool name is correct and parameters are properly formatted JSON objects.
  • Timeouts may occur during communication; adjust the HTTP timeout setting if using HTTP Streamable connection.
  • If no tools are found in the response, verify that the MCP server has tools configured and accessible.

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