AI Agent: Call n8n Workflow Tool - Invalid URL error

[Rob]

Did anyone manage to resolve this? I am trying to connect TidyCal Api.

If I use the standard (Non-Tool) HTTP Request I can get a response from TidayCal Api. But if I use the Tool HTTP Request, with the exact same setup I get invalid URL…

The Output field

Output

1 item

Invalid URL

Error details

From HTTP Request

Error code

none

Other info

Item Index

0

Run Index

0

Node type

@n8n/n8n-nodes-langchain.toolHttpRequest

Node version

1.1 (Latest)

n8n version

1.80.3 (Self Hosted)

Time

26/02/2025, 12:55:03

Stack trace

NodeApiError: Invalid URL at RoutingNode.runNode (/usr/local/lib/node_modules/n8n/node_modules/n8n-core/dist/execution-engine/routing-node.js:158:23) at processTicksAndRejections (node:internal/process/task_queues:95:5) at ExecuteContext.versionedNodeType.execute (/usr/local/lib/node_modules/n8n/dist/node-types.js:55:30) at WorkflowExecute.runNode (/usr/local/lib/node_modules/n8n/node_modules/n8n-core/dist/execution-engine/workflow-execute.js:627:19) at /usr/local/lib/node_modules/n8n/node_modules/n8n-core/dist/execution-engine/workflow-execute.js:878:51 at /usr/local/lib/node_modules/n8n/node_modules/n8n-core/dist/execution-engine/workflow-execute.js:1211:20

[Clive_Li]

I found that, the error happens when you manually run the http request tool step, if you run the whole ai agent workflow, it works.

The problem just not able to debug the httprequest

[samcha]

I encountered this issue when I added an HTTP Request tool with the URL set via a placeholder to an AI Agent. The Agent node ran the tool immediately (out of turn) and errored out.

Running the whole workflow didn’t help.

Putting the HTTP Request into a subworkflow worked.

[archi1]

@samcha

unning the whole workflow didn’t help.

I encountered the same issue and dont ask me why,I fixed the problem when i implemented an window mem. buffer.