Describe the problem/error/question
AI agent returns error of No prompt specified, but I do define the prompt and the Human Input is same as the referenced node value, then why there is no prompt specified?
What is the error message (if any)?
Node type: @n8n/n8n-nodes-langchain.agent
Node version: 3.1 (Latest)
n8n version: 2.1.5 (Self Hosted)
Time: 6/1/2026, 4:05:56 AM
Stack trace
NodeOperationError: No prompt specified at getPromptInputByType (/Users/Tech/software/node-v22.18.0-darwin-arm64/lib/node_modules/n8n/node_modules/@n8n/n8n-nodes-langchain/utils/helpers.ts:96:9) at prepareItemContext (/Users/Tech/software/node-v22.18.0-darwin-arm64/lib/node_modules/n8n/node_modules/@n8n/n8n-nodes-langchain/nodes/agents/Agent/agents/ToolsAgent/V3/helpers/prepareItemContext.ts:43:16) at /Users/Tech/software/node-v22.18.0-darwin-arm64/lib/node_modules/n8n/node_modules/@n8n/n8n-nodes-langchain/nodes/agents/Agent/agents/ToolsAgent/V3/helpers/executeBatch.ts:60:29 at Array.map (<anonymous>) at executeBatch (/Users/Tech/software/node-v22.18.0-darwin-arm64/lib/node_modules/n8n/node_modules/@n8n/n8n-nodes-langchain/nodes/agents/Agent/agents/ToolsAgent/V3/helpers/executeBatch.ts:55:30) at ExecuteContext.toolsAgentExecute (/Users/Tech/software/node-v22.18.0-darwin-arm64/lib/node_modules/n8n/node_modules/@n8n/n8n-nodes-langchain/nodes/agents/Agent/agents/ToolsAgent/V3/execute.ts:46:72) at ExecuteContext.execute (/Users/Tech/software/node-v22.18.0-darwin-arm64/lib/node_modules/n8n/node_modules/@n8n/n8n-nodes-langchain/nodes/agents/Agent/V3/AgentV3.node.ts:139:10) at WorkflowExecute.executeNode (/Users/Tech/software/node-v22.18.0-darwin-arm64/lib/node_modules/n8n/node_modules/n8n-core/src/execution-engine/workflow-execute.ts:1045:8) at WorkflowExecute.runNode (/Users/Tech/software/node-v22.18.0-darwin-arm64/lib/node_modules/n8n/node_modules/n8n-core/src/execution-engine/workflow-execute.ts:1226:11) at /Users/Tech/software/node-v22.18.0-darwin-arm64/lib/node_modules/n8n/node_modules/n8n-core/src/execution-engine/workflow-execute.ts:1662:27
Please share your workflow
Share the output returned by the last node
Information on your n8n setup
- n8n version: 2.1.5
- Database (default: SQLite):
- n8n EXECUTIONS_PROCESS setting (default: own, main):
- Running n8n via (Docker, npm, n8n cloud, desktop app): npm
- Operating system: MacOS
