n8n node to use LangSmith prompt templates with variable substitution
npm install n8n-nodes-langsmith-promptThis is an n8n community node. It lets you use LangSmith prompt templates in your n8n workflows.
LangSmith is a platform for debugging, testing, evaluating, and monitoring LLM applications, allowing you to manage prompts and track their performance.
n8n is a fair-code licensed workflow automation platform.
Installation
Operations
Credentials
Compatibility
Usage
Resources
Follow the installation guide in the n8n community nodes documentation.
- Fill Prompt Template: Fetches a prompt template from LangSmith by name and substitutes parameter values into the template's variable placeholders.
You need a LangSmith API key to use this node.
1. Sign up for an account at LangSmith
2. Generate an API key in your account settings
3. Use this API key in the LangSmith API credentials in n8n
This node has been tested with n8n version 1.0.0 and later.
1. Add the LangSmith Prompt node to your workflow
2. Configure the LangSmith API credentials with your API key
3. Enter the Prompt Name of the prompt template you want to fetch from LangSmith
4. Add Input Parameters to substitute in the template:
- Click "Add Parameter" to add key-value pairs
- For each parameter, provide:
- Name: The parameter name as it appears in the template (e.g., if template contains {question}, use "question")
- Value: The value to substitute for that parameter
If your LangSmith prompt template is:
``text`
This is your question: "{Question}"
And you add a parameter with:
- Name: Question
- Value: What is artificial intelligence?
The filled template output will be:
`text`
This is your question: "What is artificial intelligence?"
If your template has multiple variables like:
`text`
Hello {Name}, your question about {Topic} is: "{Question}"
Add three parameters:
- Name: Name, Value: John
- Name: Topic, Value: Machine Learning
- Name: Question, Value: How do neural networks work?
The node outputs an object with the prompt name as key and the filled prompt content as value:
`json`
{
"my-template": "This is your question: \"What is artificial intelligence?\""
}
You can reference this output in subsequent nodes using expressions such as:
`javascript``
{{$node["LangSmith Prompt"].json["my-template"]}}
Where "my-template" is the name of your prompt.
- n8n community nodes documentation
- LangSmith documentation
- LangSmith API reference