Workflow Extensions

This example demonstrates how workflows can extend other workflows and use arguments for customization. We’ll build a report generation workflow that can be extended by other workflows with customizable content and additional features.

Note: This example uses create_mock tools for demonstration purposes to keep the example simple and focused on core workflow concepts. In real-world use cases, you would replace these mock tools with actual tools that perform the specific processing operations your automation requires (such as API calls, data transformations, file operations, or LLM interactions).

Base Workflow Definition

The base workflow defines a reusable report generation pattern with configurable arguments:


workflows:
  - name: generate_base_report
    title: "Base Report Generation Workflow"
    type: stateMachine
    parameters:       # Argument definitions (JSON schema) for validation
      type: object
      properties:
        topic:
          type: string
          minLength: 1
          description: "The topic or subject for the report"
        report_type:
          type: string
          enum: ["quarterly", "annual", "project", "analysis"]
          default: "analysis"
          description: "Type of report to generate"
        audience:
          type: string
          enum: ["executives", "managers", "technical", "general"]
          default: "general"
          description: "Target audience for the report"
      required:
        - topic
    transitions:
      - name: generate_report
        from: start
        to: report_generated
        call:
          - tool: create_mock
            arguments:
              input: |
                You are a professional report writer. Create a comprehensive {{ arguments.report_type }} report
                for a {{ arguments.audience }} audience. The report should be well-structured with clear sections,
                data analysis, and actionable insights.
 
                Generate a detailed report about: {{ arguments.topic }}
              output: |
                # Renewable Energy Market Trends - Q4 2024 Executive Report
 
                ## Executive Overview
                The renewable energy sector has demonstrated unprecedented growth in 2024, with solar and wind technologies leading market expansion. Global renewable capacity increased by 15% year-over-year, driven by favorable policy frameworks and declining technology costs.
 
                ## Key Market Developments
                - Solar photovoltaic installations grew by 22% globally
                - Offshore wind capacity expanded by 18% in key markets
                - Energy storage deployment increased by 35%
                - Grid modernization investments reached $180 billion
                - Cost competitiveness improved with solar LCOE decreasing by 8%
                - Wind LCOE decreased by 6% while battery storage costs fell by 15%
            as: REPORT_CONTENT
 
          - tool: create_chat_message
            arguments:
              role: 'assistant'
              content: ${ REPORT_CONTENT }
 
      - name: complete_report
        from: report_generated
        to: end
        call:
          - tool: create_chat_message
            arguments:
              role: 'assistant'
              content: '📊 Report generation completed!'

Extending Base Workflow

The workflow extends the base workflow, provides arguments, and adds custom transitions:


workflows:
  - name: generate_full_report
    title: "Report Generation with Executive Summary"
    type: stateMachine
    extends: generate_base_report      # Extend the base workflow
    arguments:                         # Set arguments for base workflow
      topic: "renewable energy market trends in 2024"
      report_type: "quarterly"
      audience: "executives"
    transitions:
 
      # Override the completion transition to add summary generation
      - name: complete_report
        from: report_generated
        to: summary_generated
        call:
          - tool: create_mock
            arguments:
              input: |
                You are an expert at creating executive summaries. Create a concise,
                high-level summary that captures the key findings, insights, and
                recommendations from the full report. Focus on actionable information
                for executive decision-making.
 
                Create an executive summary for this report:
                {{ REPORT_CONTENT }}
              output: |
                ## Executive Summary
 
                **Growth Overview:** The renewable energy sector achieved exceptional 15% capacity expansion in 2024, with solar and wind technologies driving market leadership through improved cost competitiveness and supportive policy frameworks.
 
                **Market Highlights:** Solar installations surged 22% globally while offshore wind expanded 18%. Energy storage deployment accelerated by 35%, supported by $180 billion in grid modernization investments and significant cost reductions across all technologies.
            as: EXECUTIVE_SUMMARY
 
          - tool: create_chat_message
            arguments:
              role: 'assistant'
              content: ${ EXECUTIVE_SUMMARY }
 
      # Add final completion transition
      - name: log_results
        from: summary_generated
        to: end
        call:
          - tool: create_chat_message
            arguments:
              role: 'assistant'
              content: |
                📋 Complete report with executive summary finished!
 
                **Topic**: {{ arguments.topic }}
                **Full Report:** {{ REPORT_CONTENT.length }} characters
                **Executive Summary:** {{ EXECUTIVE_SUMMARY.length }} characters

The extended workflow creates an enhanced flow with executive summary:

Before:

After:

Understanding Workflow Extension

Parameters


workflows:
  - name: generate_base_report
    type: stateMachine
    parameters:                     # JSON Schema for arguments validation
      type: object
      properties:
        topic:
          type: string
          minLength: 1
          description: "The topic or subject for the report"
        report_type:
          type: string
          enum: ["quarterly", "annual", "project", "analysis"]
          default: "analysis"
        audience:
          type: string
          enum: ["executives", "managers", "technical", "general"]
          default: "general"
      required:
        - topic
    transitions:
      # Workflow logic using arguments

Key Concepts:

Parameters Schema: Define validation rules for arguments using JSON Schema
Arguments Access: Use {{ arguments.propertyName }} to access provided arguments
Validation: Arguments are validated against the parameters schema

Extends and Arguments


workflows:
  - name: generate_full_report
    extends: generate_base_report                              # Inherit base workflow
    arguments:                                                 # Provide validated arguments
      topic: "renewable energy market trends in 2024"
      report_type: "quarterly"
      audience: "executives"
    transitions:                                               # Override or extend transitions
      - name: complete_report                                  # Override base transition
        # Custom implementation with summary generation

Key Concepts:

Extension: Workflows extend other workflows
Arguments: Provide arguments to be used in extended workflows
Transitions: Add or override transitions

Workflow Extension Patterns

Pure Extension (Arguments Only)

In this pattern we use a workflow by defining arguments but do not override or extend their transitions.


workflows:
  - name: simple_report_workflow
    extends: generate_base_report
    arguments:
      topic: "market analysis for Q3 2024"
      report_type: "analysis"
      audience: "managers"
    # No transitions - uses base workflow as-is

Extension with Override

We can override existing transitions by defining a transition with the same name in the parent workflow.


workflows:
  - name: technical_report_workflow
    extends: generate_base_report
    arguments:
      topic: "system architecture review"
      report_type: "project"
      audience: "technical"
    transitions:
      - name: generate_report      # Override base implementation
        from: start
        to: report_generated
        call:
          - tool: technical_report_generator

Extension with Additional Transitions

We can add new transitions (new name)


workflows:
  - name: reviewed_report_workflow
    extends: generate_base_report
    arguments:
      topic: "compliance audit findings"
      report_type: "annual"
      audience: "executives"
    transitions:
      - name: requestReview       # Add new transition
        from: end
        to: underReview
        call:
          - tool: review_request_tool

Key Concepts:

Flexible Extension: Multiple ways to extend base workflows
Arguments Inheritance: Extensions use a merged arguments schema (when working with nested workflows)
Selective Customization: Override only what needs to be different

Multiple Workflow Extensions

Different workflows can extend the same base workflow for various report types:


# base workflow
workflows:
  - name: base_workflow
    parameters:
      ...                         # Define base_workflow parameters
    transitions:
      ...
 
  # extending workflow 1
  - name: extending_workflow_1
    extends: base_workflow
    arguments:                    # Set arguments for base_workflow
     ...
 
  # extending workflow 2
  - name: extending_workflow_2
    extends: base_workflow
    arguments:                    # Set arguments for base_workflow
      ...

Multi-Level Workflow Extension

Workflows can create inheritance chains where a workflow extends another workflow that extends yet another workflow. The system merges schemas, transitions, and other properties across the entire inheritance hierarchy before execution.


# Base workflow
workflows:
  - name: base_workflow
    type: stateMachine
    parameters:
      ...                         # Define base_workflow parameters
    transitions:
      ...
 
  # workflow extending base_workflow
  - name: extending_workflow
    extends: base_workflow
    parameters:
      ...                         # Define own properties to be merged with base_workflow properties
    transitions:
      ...                         # Override or extend base transitions
 
  # workflow extending extending_workflow
  - name: final_workflow
    extends: base_workflow
    parameters:
      ...                         # Define own properties to be merged with extending_workflow properties
    arguments:
      ...                         # Set arguments for all workflows
    transitions:
      ...                         # Override or extend base transitions

During execution, Loopstack merges the inheritance chain into a single workflow. The outer workflow needs to define the arguments for all inherited workflows.

Running This Example

This example is already available in Loopstack Studio:

Navigate to the Studio interface
Switch to the examples workspace
Select “Example 4: Workflow Extensions” from the available automations
Observe how the base workflow’s generate_report transition executes first
See the overridden complete_report transition that generates an executive summary
Notice the additional log_results transition with detailed metrics

Configuration Location: You can also view the complete configuration file at src/config/examples/basic/workflow-extension-example.yaml

Complete Example:


include:
  - core/tools/create-mock.yaml
  - core/tools/create-chat-message.yaml
  - core/tools/create-document.yaml
  - core/tools/switch-target.yaml
 
pipelines:
  - name: human_in_the_loop_example
    title: "Example 7: Human-in-the-Loop Workflow"
    type: root
    workspace: examples
    sequence:
      - workflow: blog_post_review
 
workflows:
  - name: blog_post_review
    type: stateMachine
    transitions:
      - name: create_draft         # Step 1: Generate initial content draft
        from: start
        to: draft_created
        call:
          - tool: create_mock
            arguments:
              input: 'blog post about renewable energy'
              output: |
                # The Future of Renewable Energy
 
                Renewable energy sources are becoming increasingly important as we work toward a sustainable future. Solar and wind power have seen dramatic cost reductions, making them competitive with traditional fossil fuels.
 
                Key benefits include:
                - Reduced carbon emissions
                - Energy independence
                - Long-term cost savings
 
                The transition to renewable energy represents one of the most significant opportunities of our time.
            as: DRAFT_CONTENT
 
          - tool: create_chat_message
            arguments:
              role: 'assistant'
              content: 'Draft content has been generated and is ready for your review.'
 
      - name: show_approval_form    # Step 2: Present draft to user for approval
        from: draft_created
        to: waiting_for_approval
        call:
          - tool: create_document
            arguments:
              document: approval_form
              content:
                draft_content: ${ DRAFT_CONTENT }
                approved: false
                feedback: ""
 
      - name: process_approval       # Step 3: Handle user's approval decision
        from: waiting_for_approval
        to:
          - approved
          - needs_revision
        when: manual                # Wait for user interaction
        call:
          - tool: create_mock
            arguments:
              input: ${ transition.payload }
              output: ${ transition.payload.approved }
            as: USER_DECISION
 
          - tool: switch_target
            arguments:
              target: "{{#if (eq USER_DECISION true)}}approved{{else}}needs_revision{{/if}}"
 
      # Approval path
      - name: finalize_content       # Handle approved content
        from: approved
        to: end
        call:
          - tool: create_mock
            arguments:
              input: ${ DRAFT_CONTENT }
              output: 'Content published successfully to blog.example.com'
            as: PUBLISH_RESULT
 
          - tool: create_chat_message
            arguments:
              role: 'assistant'
              content: |
                ✅ Content approved and published!
                
                {{ PUBLISH_RESULT }}
 
      # Revision path
      - name: handle_revision        # Handle revision requests
        from: needs_revision
        to: draft_created            # Return to draft creation for revision
        call:
          - tool: create_chat_message
            arguments:
              role: 'assistant'
              content: '📝 Revision requested. Generating updated draft with your feedback...'
 
          - tool: create_mock
            arguments:
              input: ${ DRAFT_CONTENT }
              output: |
                # The Future of Renewable Energy (Revised)
 
                Renewable energy sources are rapidly transforming our global energy landscape. Solar and wind power have experienced unprecedented cost reductions, making them not just environmentally responsible but economically superior to traditional fossil fuels.
 
                Key benefits include:
                - Significant reduction in carbon emissions
                - Enhanced energy independence and security
                - Substantial long-term cost savings
                - Job creation in emerging green industries
 
                The transition to renewable energy represents the most transformative opportunity of our generation, offering both environmental and economic advantages.
            as: DRAFT_CONTENT
 
documents:
  - name: approval_form
    schema:
      type: object
      properties:
        draft_content:
          type: string
        approved:
          type: boolean
        feedback:
          type: string
      required:
        - draft_content
        - approved
    ui:
      properties:
        draft_content:
          widget: textarea-expand
          title: "Draft Content"
          readonly: true
        approved:
          widget: switch
          title: "Approve"
        feedback:
          widget: textarea
          title: "Feedback (optional)"
          placeholder: "Provide feedback for revisions..."
      order:
        - draft_content
        - feedback
        - approved
      buttons:
        - transition: process_approval
          label: "Submit Decision"
          enabledWhen:
            - waiting_for_approval