> For the complete documentation index, see [llms.txt](https://doc.duaer.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.duaer.com/integrations/builtin/core-nodes/n8n-nodes-langchain.mcptrigger.md).

# Use Duaer Server Trigger in Duaer

Duaer Server Trigger in Duaer is a built-in core node for data or flow control without an external SaaS account. Node note: Expose Duaer tools as a Duaer Server endpoint
## Duaer Server Trigger in Duaer

Duaer Server Trigger is a built-in core node in Duaer for data or flow control. It usually does not need an external SaaS credential.

The product’s node note is: Expose Duaer tools as a Duaer Server endpoint.

## Credentials and parameters

Most core nodes do not need an external credential. If the node still asks for one, create it from the fields it shows.

Parameters accept expressions. Tool parameters that an AI Agent should fill use $fromAI. When a run fails, read the error on the node output first.
## Questions

### How do you add Duaer Server Trigger to a Duaer digital organization?

Open the node panel on the Duaer canvas, search for Duaer Server Trigger, and drop it onto the digital organization. Connect it after a trigger or a previous node.

### What should you check first when Duaer Server Trigger fails in Duaer?

Read the error text on that node’s output, then confirm the credential still works and required parameters are filled. For app nodes, also check permissions and quota on the provider side.