nebulaflow

Node Types Overview

NebulaFlow provides several types of nodes that you can use to build workflows. Each node type serves a specific purpose in the execution flow.

Agent Nodes

LLM Node (Agent Node)

• Purpose: Interact with Large Language Models for AI-powered tasks
• Inputs: Previous node output (text or data)
• Outputs: Generated text from the LLM
• Configuration:
  • Model selection (via OpenRouter or Amp SDK)
  • Prompt template with variable substitution
  • System prompt template
  • Reasoning effort (minimal, low, medium, high)
  • Timeout settings
  • Tool usage permissions
  • Attachments (images)
• Category: Agent

Text Nodes

Text Node (Input Node)

• Purpose: Provide input text or data to the workflow
• Inputs: None (or previous node output)
• Outputs: Text content
• Configuration:
  • Text content (editable)
  • Active/inactive state
  • Fan-in support (multiple inputs)
• Category: Text

Accumulator Node

• Purpose: Collect and accumulate data from multiple inputs
• Inputs: Multiple previous nodes
• Outputs: Accumulated result
• Configuration:
  • Variable name for storage
  • Initial value
  • Fan-in support (multiple inputs)
• Category: Text

Variable Node

• Purpose: Store and manage workflow variables
• Inputs: Previous node output
• Outputs: Variable value
• Configuration:
  • Variable name
  • Initial value
• Category: Text

Shell Nodes

CLI Node (Shell Node)

• Purpose: Execute shell commands and scripts
• Inputs: Previous node output
• Outputs: Command output and exit code
• Configuration:
  • Command to execute
  • Arguments
  • Working directory
  • Environment variables
  • Timeout settings
  • Shell selection (bash, sh, zsh, pwsh, cmd)
  • Safety level (safe, advanced)
  • Stream output option
  • Flags (exitOnError, pipefail, etc.)
  • Stdin configuration
• Category: Shell

Conditionals Nodes

If/Else Node (Condition Node)

• Purpose: Branch workflow based on conditions
• Inputs: Previous node output
• Outputs: True/False branches
• Configuration:
  • Condition expression
  • Comparison operator
  • Value to compare against
  • Path activation states
• Category: Conditionals

Loops Nodes

Loop Start Node

• Purpose: Begin a loop iteration
• Inputs: Previous node output
• Outputs: Loop body execution
• Configuration:
  • Iteration count
  • Loop variable name
  • Loop mode (fixed, while-variable-not-empty)
  • Collection variable (for foreach)
  • Maximum safe iterations
  • Override iterations option
• Category: Loops

Loop End Node

• Purpose: End a loop iteration
• Inputs: Loop body output
• Outputs: Next node after loop
• Configuration: None required
• Category: Loops

Preview Nodes

Preview Node

• Purpose: Display intermediate results for debugging
• Inputs: Previous node output
• Outputs: Passthrough (original data)
• Configuration:
  • Content display
  • Active/inactive state
• Category: Preview

Subflows Nodes

Subflow Node

• Purpose: Execute a nested workflow
• Inputs: Previous node output
• Outputs: Subflow results
• Configuration:
  • Subflow ID reference
  • Input port count
  • Output port count
  • Pending subflow definition
• Category: Subflows

Subflow Input Node (Internal)

• Purpose: Define input ports for subflow (internal only)
• Inputs: None
• Outputs: Input data to subflow
• Configuration:
  • Port ID
  • Port name
  • Port index
• Category: Subflows (internal)

Subflow Output Node (Internal)

• Purpose: Define output ports for subflow (internal only)
• Inputs: Subflow execution result
• Outputs: Output data from subflow
• Configuration:
  • Port ID
  • Port name
  • Port index
• Category: Subflows (internal)

Node Connections

Visual Connections

• Drag from output port to input port to create edges
• Nodes connect automatically when dropped near each other
• Multiple connections supported for branching and fan-in patterns
• Subflow nodes support dynamic input/output ports

Data Flow

• Output from one node becomes input to the next
• Data flows sequentially through the workflow
• Branching allows parallel execution paths
• Fan-in patterns allow multiple nodes to feed into a single node (e.g., Accumulator)
• Subflows encapsulate complex workflows

Node Configuration

Property Editor

• Click any node to open the property editor
• Configure node-specific settings
• Use variables and expressions where supported
• Changes apply immediately
• Some nodes require user approval before execution

Variable Support

• Reference parent node outputs using ${1}, ${2}, etc. (by connection order)
• Reference variables stored by Variable or Accumulator nodes using ${variableName}
• Loop iteration counter is available as ${i} (or custom loop variable name)
• Environment variables can be mapped in CLI nodes via environment configuration
• Variable nodes store persistent values across workflow execution

Best Practices

Node Naming

• Give nodes descriptive names
• Use consistent naming conventions
• Add comments for complex logic
• Use meaningful titles for LLM prompts

Error Handling

• Add If/Else nodes for conditional branching
• Use Preview nodes for debugging intermediate results
• Check node execution states (executing, error, interrupted)
• Monitor token counts for LLM nodes

Performance

• Avoid unnecessary loops
• Use loop iteration limits for safety
• Batch operations when possible
• Consider fan-in patterns for data aggregation

Testing

• Test nodes individually using single-node execution
• Validate data flows between nodes
• Check edge cases in conditional logic
• Use Preview nodes to inspect data at any point

Execution Model

Streaming Execution

• LLM and CLI nodes support streaming output
• Real-time event handling during execution
• Progress indicators for long-running operations
• Pause/resume capability for workflows

Approval System

• CLI nodes may require user approval before execution
• Safety levels control approval requirements
• Configurable via node properties

Parallel Execution

• Workflow engine supports parallel node execution
• Automatic dependency analysis
• Configurable concurrency limits per node type

Node Properties

Each node has common properties:

• ID: Unique identifier (auto-generated)
• Name: Display name (editable)
• Position: X/Y coordinates on canvas
• Data: Node-specific configuration
• Active: Enable/disable node execution
• Bypass: Skip node during execution (passthrough)
• Needs User Approval: Requires approval before execution
• Token Count: Track LLM token usage
• Executing: Current execution state
• Error: Error state indicator
• Interrupted: Paused/stopped state

Next Steps

• LLM Nodes - Deep dive into LLM node configuration
• CLI Nodes - Learn about shell command execution
• Condition Nodes - Master conditional logic
• Loop Nodes - Understand iteration patterns
• Workflow Design - Design effective workflows

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