feat: add Sub-Agent creation dialog with deferred file creation by breaking-brake · Pull Request #646 · breaking-brake/cc-wf-studio

breaking-brake · Mar 16, 2026

Summary

Add a Sub-Agent creation dialog that supports both "Create New" and "Use Existing" flows, plus deferred file creation in the DiffPreviewDialog for MCP apply_workflow.

Closes #636

Motivation

CC Workflow Studio previously only supported inline Sub-Agent definitions. Users with existing .claude/agents/*.md command files had to recreate them manually. Additionally, apply_workflow wrote Sub-Agent .md files to disk before user review — rejected changes left orphan files.

Changes

New Files:

src/webview/src/components/dialogs/SubAgentCreationDialog.tsx - Browse/create dialog with two tabs (Create New / Use Existing)
src/webview/src/components/dialogs/SubAgentFormDialog.tsx - Form for creating new sub-agent with all fields
src/webview/src/services/command-browser-service.ts - Service for browsing .claude/agents/ commands
src/extension/commands/command-operations.ts - Extension host handlers for command scanning
src/extension/services/command-service.ts - Command file scanner (user/project scopes)
src/extension/utils/path-utils.ts - Path utilities for .claude/agents/ directories

Modified Files:

src/extension/services/mcp-server-tools.ts - Split autoCreateSubAgentFiles into planSubAgentFiles (no disk write) + executeSubAgentFileCreation (post-approval)
src/extension/services/mcp-server-service.ts - Pass plannedFiles through MCP payload
src/shared/types/messages.ts - Add PlannedSubAgentFile type and message types for command scanning
src/webview/src/components/dialogs/DiffPreviewDialog.tsx - Add "Files to be created" section
src/webview/src/App.tsx - Wire plannedFiles to DiffPreviewDialog
resources/workflow-schema.json / .toon - Add commandFilePath, commandScope, agentType, aiGenerationGuidance
resources/ai-editing-skill-template.md - Add list_available_commands step
src/extension/utils/validate-workflow.ts - Add commandScope validation
src/extension/services/export-service.ts - Reference model support in export
i18n files (en/ja/ko/zh-CN/zh-TW) - Translation keys for new dialogs and file preview

Testing

Manual E2E testing completed
npm run format && npm run lint && npm run check && npm run build passes

🤖 Generated with Claude Code

Summary by CodeRabbit

Release Notes

New Features
- Added Sub-Agent creation workflow with browsing and selection of existing command files.
- Introduced ability to discover and reuse available agent commands from existing repositories.
- Enhanced workflow application preview to show planned file creations before applying.
Improvements
- Added Sub-Agent editing dialog with support for agent type configuration and customization.
- Improved workflow validation to properly handle linked vs. inline Sub-Agent definitions.
- Enhanced UI with tool selection sizing options and improved property display.
Documentation
- Updated workflow template with refined discovery and application steps.
- Added comprehensive translations for Sub-Agent features across multiple languages.

- Add SubAgentCreationDialog for browsing existing .claude/commands - Add SubAgentFormDialog for creating new Sub-Agent nodes - Add command-browser-service and command-operations - Move "Create New" buttons next to filter input in both SubAgent and Skill dialogs - Change SubAgent dialog title to "Browse Sub-Agent" - Set default model to "Inherit" for new Sub-Agent creation - Add i18n translations for all Sub-Agent dialog strings (en/ja/ko/zh-CN/zh-TW) Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

…Dialog - Split autoCreateSubAgentFiles into planSubAgentFiles + executeSubAgentFileCreation - Add PlannedSubAgentFile type and pass plannedFiles through MCP payload - Show "Files to be created" section in DiffPreviewDialog with file paths - Add schema fields (commandFilePath, commandScope, agentType, aiGenerationGuidance) - Add commandScope validation and export-service reference model support Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

coderabbitai · Mar 16, 2026

Caution

Review failed

Pull request was closed or merged during review

📝 Walkthrough

Walkthrough

This PR extends the workflow system to support reusing existing sub-agents from external command definitions. It adds command discovery services, new MCP tools for listing available commands, planning/creation workflows for sub-agent files, linked command referencing, and corresponding UI components for browsing, selecting, and creating sub-agents with field support for agentType, commandFilePath, and commandScope.

Changes

Cohort / File(s)	Summary
Schema & Documentation `resources/ai-editing-skill-template.md`, `resources/workflow-schema.json`, `resources/workflow-schema.toon`	Reorders workflow discovery steps, adds aiGenerationGuidance blocks, and introduces subAgent fields: agentType, commandFilePath, commandScope for external agent linking; mirrors guidance structure in subAgentFlow.
Command Discovery Services `src/extension/services/command-service.ts`, `src/extension/utils/path-utils.ts`	New command scanning utilities that discover and aggregate .md command files from user and project .claude/agents directories, extracting metadata (name, description, scope) for reuse.
MCP Server Tools & Planning `src/extension/services/mcp-server-tools.ts`, `src/extension/services/export-service.ts`, `src/extension/services/mcp-server-service.ts`	Adds list_available_commands MCP tool, planning phase (planSubAgentFiles) to resolve new sub-agents with generated commandFilePath values, and post-apply file creation (executeSubAgentFileCreation); skip inline sub-agents during export.
Sub-Agent File Creation Handlers `src/extension/commands/command-operations.ts`, `src/extension/commands/open-editor.ts`	New handlers (handleBrowseCommands, handleCreateSubAgent) for webview communication; scan and return command lists, create/edit sub-agent markdown files with appropriate error handling and logging.
Shared Message Types & Workflow Definition `src/shared/types/messages.ts`, `src/shared/types/workflow-definition.ts`, `src/extension/utils/validate-workflow.ts`	Introduces CommandReference, CreateSubAgentPayload, SubAgentCreationSuccessPayload, CommandListLoadedPayload, PlannedSubAgentFile types; extends SubAgentData with agentType, commandFilePath, commandScope; adds commandScope validation.
Sub-Agent UI Dialogs & Components `src/webview/src/components/dialogs/SubAgentCreationDialog.tsx`, `src/webview/src/components/dialogs/SubAgentFormDialog.tsx`, `src/webview/src/components/dialogs/DiffPreviewDialog.tsx`	New dialog components for browsing existing commands and creating sub-agents with form validation; DiffPreviewDialog extended to display planned file creation previews.
Webview Integration & State Management `src/webview/src/App.tsx`, `src/webview/src/components/NodePalette.tsx`, `src/webview/src/components/PropertyOverlay.tsx`, `src/webview/src/services/command-browser-service.ts`	Propagates plannedFiles through MCP apply flow, integrates sub-agent creation dialogs, adds command selection and form-based creation handlers with frontmatter parsing; new service for command browsing and sub-agent creation requests.
UI Refinements `src/webview/src/components/common/ColorPicker.tsx`, `src/webview/src/components/common/ToolSelectTagInput.tsx`, `src/webview/src/components/dialogs/SkillBrowserDialog.tsx`	Increases z-index, adds size-based styling system and configurable tool list, relocates Create button to filter row.
Internationalization `src/webview/src/i18n/translation-keys.ts`, `src/webview/src/i18n/translations/en.ts`, `src/webview/src/i18n/translations/ja.ts`, `src/webview/src/i18n/translations/ko.ts`, `src/webview/src/i18n/translations/zh-CN.ts`, `src/webview/src/i18n/translations/zh-TW.ts`	Extensive new translation keys for sub-agent creation dialogs, form fields, labels, and validation messages across all supported languages.

Sequence Diagram

sequenceDiagram
    participant User
    participant Webview
    participant Extension as Extension Host
    participant FileSystem as File System
    
    User->>Webview: Click "Browse Existing Sub-Agents"
    Webview->>Webview: Open SubAgentCreationDialog
    Webview->>Extension: BROWSE_COMMANDS (requestId)
    Extension->>FileSystem: Scan ~/.claude/agents/*.md
    Extension->>FileSystem: Scan {workspace}/.claude/agents/*.md
    FileSystem-->>Extension: List of .md files
    Extension->>Extension: Extract metadata (name, description, promptContent)
    Extension-->>Webview: COMMAND_LIST_LOADED (CommandReference[], counts)
    Webview->>Webview: Render filtered command list by scope
    
    User->>Webview: Select command or choose "Create New"
    
    alt User selects existing command
        Webview->>Webview: Parse frontmatter from command.promptContent
        Webview->>Webview: Populate SubAgent node data
    else User creates new sub-agent
        User->>Webview: Fill SubAgentFormDialog (description, prompt, model, tools, memory)
        Webview->>Extension: CREATE_SUB_AGENT (CreateSubAgentPayload)
        Extension->>FileSystem: Write .claude/agents/{name}.md
        FileSystem-->>Extension: File created
        Extension-->>Webview: SUB_AGENT_CREATION_SUCCESS (filePath)
    end
    
    Webview->>Webview: Add SubAgent node with commandFilePath reference
    Webview->>Webview: Workflow now includes linked sub-agent

Estimated code review effort

🎯 4 (Complex) | ⏱️ ~75 minutes

Possibly related issues

Add support for existing sub-agents in CC Workflow Studio #636: Add support for existing sub-agents in CC Workflow Studio — This PR directly implements the proposed solution by enabling discovery and reuse of existing sub-agents through command file scanning, linked command referencing (commandFilePath), and UI workflows for browsing and importing external sub-agents into the editor.

Suggested labels

released

Poem

🐰 A rabbit hops through .claude/agents/ fine,
Gathering commands from user and project's line,
Sub-agents now linked, no rebuild in sight,
Workflow reuse makes the ecosystem bright! ✨

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The PR title accurately summarizes the main change: adding a Sub-Agent creation dialog with deferred file creation, which aligns with the primary objectives.
Linked Issues check	✅ Passed	The PR implements the core objectives from `#636`: discovering existing sub-agents, displaying them in a UI, allowing selection/reuse, and supporting both linked and inline modes with proper schema and workflow support.
Out of Scope Changes check	✅ Passed	All changes are directly related to the Sub-Agent discovery and creation feature. Minor improvements like ColorPicker z-index and ToolSelectTagInput size props are supporting enhancements integral to the new Sub-Agent UI.
Docstring Coverage	✅ Passed	Docstring coverage is 85.71% which is sufficient. The required threshold is 80.00%.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

📝 Generate docstrings (stacked PR)
📝 Generate docstrings (commit on current branch)

🧪 Generate unit tests (beta)

Create PR with unit tests
Post copyable unit tests in a comment
Commit unit tests in branch feat/sub-agent-creation-dialog

📝 Coding Plan

Generate coding plan for human review comments

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

Tip

You can disable sequence diagrams in the walkthrough.

Disable the reviews.sequence_diagrams setting to disable sequence diagrams in the walkthrough.

## [3.28.0](v3.27.1...v3.28.0) (2026-03-16) ### Features * add Sub-Agent creation dialog with deferred file creation ([#646](#646)) ([f6d8b9f](f6d8b9f))

braking-brake-semantic-release · Mar 16, 2026

🎉 This PR is included in version 3.28.0 🎉

The release is available on GitHub release

Your semantic-release bot 📦🚀

breaking-brake and others added 2 commits March 16, 2026 00:31

breaking-brake merged commit f6d8b9f into main Mar 16, 2026
3 of 4 checks passed

breaking-brake deleted the feat/sub-agent-creation-dialog branch March 16, 2026 11:54

breaking-brake mentioned this pull request Mar 16, 2026

Release: v3.28.0 #648

Merged

braking-brake-semantic-release Bot added the released label Mar 16, 2026

This was referenced Mar 19, 2026

feat: add group node highlight toggle, MCP improvements, and bug fixes #661

Merged

fix: support plugin agents in workflow detection and export (#651) #663

Merged

This was referenced Mar 26, 2026

feat: add built-in sub-agent presets with cross-platform export support #686

Merged

improvement: separate Agent Definition and Prompt in Sub-Agent node #687

Merged

This was referenced Apr 2, 2026

feat: add undo/redo for canvas nodes and edges #699

Merged

improvement: add canvas revision tracking for optimistic concurrency control #702

Merged

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

feat: add Sub-Agent creation dialog with deferred file creation#646

feat: add Sub-Agent creation dialog with deferred file creation#646
breaking-brake merged 2 commits intomainbreaking-brake/cc-wf-studio:mainfrom
feat/sub-agent-creation-dialogbreaking-brake/cc-wf-studio:feat/sub-agent-creation-dialogCopy head branch name to clipboard

breaking-brake commented Mar 16, 2026 •

edited by coderabbitai Bot

Loading

Uh oh!

coderabbitai Bot commented Mar 16, 2026 •

edited

Loading

Review failed

Walkthrough

Changes

Sequence Diagram

Estimated code review effort

Possibly related issues

Suggested labels

Poem

Uh oh!

Uh oh!

braking-brake-semantic-release Bot commented Mar 16, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

1 participant

Search code, repositories, users, issues, pull requests...

Conversation

breaking-brake commented Mar 16, 2026 • edited by coderabbitai Bot Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Summary

Motivation

Changes

Testing

Summary by CodeRabbit

Release Notes

Uh oh!

coderabbitai Bot commented Mar 16, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Review failed

Walkthrough

Changes

Sequence Diagram

Estimated code review effort

Possibly related issues

Suggested labels

Poem

Uh oh!

Uh oh!

braking-brake-semantic-release Bot commented Mar 16, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

1 participant

breaking-brake commented Mar 16, 2026 •

edited by coderabbitai Bot

Loading

coderabbitai Bot commented Mar 16, 2026 •

edited

Loading