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Usage Guide

Node Parameters

Base URL

The URL of your Pipelex API server.

Examples:

  • Local Docker: http://localhost:8081 or http://host.docker.internal:8081
  • Remote server: https://api.yourserver.com
  • Public Pipelex API: (Coming Soon, join the waitlist here)

Understanding pipe_code and plx_content

The Pipelex node offers flexibility in how you define and execute pipelines. You can either reference a pre-registered pipeline, provide inline PLX code, or combine both approaches.

Case 1: Only pipe_code (Pipeline Library)

Use this when your pipeline is already registered in your Pipelex API server's library.

n8n Node Configuration: - Pipe Code: invoice_extractor - Pipelex Bundle: (leave empty) - Inputs: { "invoice_text": "..." }

What happens: The API will look for a pipeline named invoice_extractor in your server's library and execute it.

API Request: 

{
  "pipe_code": "invoice_extractor",
  "inputs": {
    "invoice_text": "INVOICE #123..."
  }
}

Use this when: - You have pipelines uploaded to your server - You want to reuse the same pipeline across multiple workflows - You prefer centralized pipeline management

Case 2: Only plx_content (Inline Pipeline)

Use this when you want to define the pipeline directly in the n8n node.

n8n Node Configuration: - Pipe Code: (leave empty) - Pipelex Bundle: 

domain = "invoice_processing"
main_pipe = "extract_invoice"

[concept]
InvoiceText = "Raw invoice text"
InvoiceData = "Structured invoice data"

[pipe.extract_invoice]
type = "PipeLLM"
inputs = { text = "InvoiceText" }
output = "InvoiceData"
model = "llm_to_extract_info"
prompt = """
Extract structured data from:
@text
"""
- Inputs: { "text": "..." }

What happens: The API will parse your inline PLX code and execute the pipeline specified in main_pipe.

API Request: 

{
  "plx_content": "domain = \"invoice_processing\"\nmain_pipe = \"extract_invoice\"...",
  "inputs": {
    "text": "INVOICE #123..."
  }
}

Important: You must specify main_pipe in your PLX content when not providing a pipe_code.

Use this when: - You're prototyping or testing pipelines - You want the pipeline definition visible in n8n - You don't have access to upload to the server library

Case 3: Both pipe_code AND plx_content (Inline with Specific Pipe)

Use this when you have multiple pipes in your inline PLX code and want to execute a specific one.

n8n Node Configuration: - Pipe Code: extract_invoice - Pipelex Bundle: 

domain = "document_processing"
main_pipe = "analyze_document"

[concept]
DocumentText = "Raw document text"
InvoiceData = "Structured invoice data"
AnalysisResult = "Document analysis"

[pipe.extract_invoice]
type = "PipeLLM"
inputs = { text = "DocumentText" }
output = "InvoiceData"
model = "llm_to_extract_info"
prompt = "Extract invoice data from: @text"

[pipe.analyze_document]
type = "PipeLLM"
inputs = { text = "DocumentText" }
output = "AnalysisResult"
model = "llm_for_analysis"
prompt = "Analyze: @text"
- Inputs: { "text": "..." }

What happens: The API will execute the extract_invoice pipe from your inline code, ignoring the main_pipe setting.

API Request: 

{
  "pipe_code": "extract_invoice",
  "plx_content": "domain = \"document_processing\"...",
  "inputs": {
    "text": "INVOICE #123..."
  }
}

Use this when: - You have a PLX file with multiple pipes - You want to choose which pipe to execute dynamically - You want flexibility without modifying the PLX content

Inputs Parameter

📚 For comprehensive input format documentation, including all cases and advanced usage patterns, see the Pipelex API Guide: Input Format (PipelineInputs).

The inputs parameter must be a JSON object where keys match the concept names in your pipeline.

Basic Example

{
  "invoice_text": "INVOICE #INV-001\nAmount: $500",
  "customer_name": "Acme Corp"
}

Using n8n Expressions

Pass data from previous nodes:

{
  "document_text": "{{ $json.content }}",
  "file_name": "{{ $json.filename }}",
  "timestamp": "{{ $now }}"
}

From Previous Node

{
  "text": "{{ $('HTTP Request').item.json.body }}",
  "metadata": {
    "source": "{{ $json.source }}",
    "user": "{{ $json.user_id }}"
  }
}

Optional Parameters

Output Name (output_name)

Specify the name you want to give to the main pipe

Example: extracted_data

Output Multiplicity (output_multiplicity)

Controls whether the pipeline returns a single item or multiple items (array).

📚 For comprehensive multiplicity documentation, see Understanding Multiplicity.

Example: If your pipeline extracts keywords from text and is configured with output = "Keyword[]" in the PLX definition, set output_multiplicity to true to receive an array of all extracted keywords, n for a specific number of items.

Dynamic Output Concept Code (dynamic_output_concept_code)

  • dynamic_output_concept_code (string, optional): Override output concept. See more here.

Learn More