FAILED TO CONNECT/MCP ERROR 32000/HELP PLEASE

[782611]

{
"errorMessage": "Failed to execute operation: Failed to connect to MCP server: MCP error -32000: Connection closed",
"errorDetails": {},
"n8nDetails": {
"nodeName": "MCP Client",
"nodeType": "n8n-nodes-mcp.mcpClient",
"nodeVersion": 1,
"operation": "listTools",
"time": "9/24/2025, 9:16:16 AM",
"n8nVersion": "1.110.1 (Self Hosted)",
"binaryDataMode": "default",
"stackTrace": [
"NodeOperationError: Failed to execute operation: Failed to connect to MCP server: MCP error -32000: Connection closed",
" at ExecuteContext.execute (/home/node/.n8n/nodes/node_modules/n8n-nodes-mcp/nodes/McpClient/McpClient.node.ts:648:10)",
" at processTicksAndRejections (node:internal/process/task_queues:105:5)",
" at WorkflowExecute.executeNode (/usr/local/lib/node_modules/n8n/node_modules/.pnpm/n8n-core@file+packages+core_@opentelemetry+api@1.9.0_@opentelemetry+sdk-trace-base@1.30_5aee33ef851c7de341eb325c6a25e0ff/node_modules/n8n-core/src/execution-engine/workflow-execute.ts:1254:8)",
" at WorkflowExecute.runNode (/usr/local/lib/node_modules/n8n/node_modules/.pnpm/n8n-core@file+packages+core_@opentelemetry+api@1.9.0_@opentelemetry+sdk-trace-base@1.30_5aee33ef851c7de341eb325c6a25e0ff/node_modules/n8n-core/src/execution-engine/workflow-execute.ts:1428:11)",
" at /usr/local/lib/node_modules/n8n/node_modules/.pnpm/n8n-core@file+packages+core_@opentelemetry+api@1.9.0_@opentelemetry+sdk-trace-base@1.30_5aee33ef851c7de341eb325c6a25e0ff/node_modules/n8n-core/src/execution-engine/workflow-execute.ts:1760:27",
" at /usr/local/lib/node_modules/n8n/node_modules/.pnpm/n8n-core@file+packages+core_@opentelemetry+api@1.9.0_@opentelemetry+sdk-trace-base@1.30_5aee33ef851c7de341eb325c6a25e0ff/node_modules/n8n-core/src/execution-engine/workflow-execute.ts:2337:11"
]
}
}

[atomic-235]

I have same issue, but it works with docker in my case

[jonathansampson]

@atomic-235, are you also seeing this error when using n8n-nodes-mcp.mcpClient? I have not yet tested this scenario, but will certainly do so. @782611, could you share a bit more about how you have the MCP Server setup/configured in your n8n workflow?

[kabuto22-maker]

{ "errorMessage": "Nie udało się wykonać operacji: Nie udało się połączyć z serwerem MCP: Błąd MCP -32000: Połączenie zamknięte", "errorDetails": {}, "n8nDetails": { "nodeName": "Klient MCP", "nodeType": "n8n-nodes-mcp.mcpClient", "nodeVersion": 1, "operation": "listTools", "time": "24.09.2025, 09:16:16", "n8nVersion": "1.110.1 (Hosting własny)", "binaryDataMode": "default", "stackTrace": [ "NodeOperationError: Nie udało się wykonać operacji: Nie udało się połączyć z serwerem MCP: Błąd MCP -32000: Połączenie zamknięte", " at ExecuteContext.execute (/home/node/.n8n/nodes/node_modules/n8n-nodes-mcp/nodes/McpClient/McpClient.node.ts:648:10)", " at processTicksAndRejections (node:internal/process/task_queues:105:5)", " at WorkflowExecute.executeNode (/usr/local/lib/node_modules/n8n/node_modules/.pnpm/n8n-core@file+packages+core_@opentelemetry+api@ 1.9.0_@opentelemetry +sdk-trace-base@1.30_5aee33ef851c7de341eb325c6a25e0ff /node_modules/n8n-core/src/execution-engine/workflow-execute.ts:1254:8)", " w WorkflowExecute.runNode (/usr/local/lib/node_modules/n8n/node_modules/.pnpm/n8n-core@file+packages+core_@opentelemetry+api@ 1.9.0_@opentelemetry +sdk-trace-base@1.30_5aee33ef851c7de341eb325c6a25e0ff /node_modules/n8n-core/src/execution-engine/workflow-execute.ts:1428:11)", " w /usr/local/lib/node_modules/n8n/node_modules/.pnpm/n8n-core@file+packages+core_@opentelemetry+api@ 1.9.0_@opentelemetry +sdk-trace-base@1.30_5aee33ef851c7de341eb325c6a25e0ff /node_modules/n8n-core/src/execution-engine/workflow-execute.ts:1760:27", " at /usr/local/lib/node_modules/n8n/node_modules/.pnpm/n8n-core@file+packages+core_@opentelemetry+api@ 1.9.0_@opentelemetry +sdk-trace-base@1.30_5aee33ef851c7de341eb325c6a25e0ff /node_modules/n8n-core/src/execution-engine/workflow-execute.ts:2337:11" ]

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