Extension Events

Overview

The HAI Build Code Generator extension provides various events and hooks that allow you to integrate with and extend its functionality. These events are triggered at different stages of the extension lifecycle and user interactions.

Extension Lifecycle Events

Extension Activation

The extension activates when specific events occur:

ActivationEvent

Triggered when any language file is opened in the editor

ActivationEvent

Triggered when VS Code finishes its startup sequence

ActivationEvent

Triggered when the workspace contains specific files (e.g., evals.env)

Usage:

"activationEvents": [
  "onLanguage",
  "onStartupFinished",
  "workspaceContains:evals.env"
]

Extension Deactivation

When the extension deactivates, cleanup operations are performed:

Disposes of non-VS Code-specific services (via tearDown())
Disposes of VS Code-specific services (comment controllers, watchers, etc.)
Cleans up registered commands and subscriptions

Hook into deactivation:

export async function deactivate() {
  // Your cleanup code here
  await tearDown();
  disposeVscodeCommentReviewController();
}

User Interaction Events

Button Click Events

The extension provides event handlers for sidebar button interactions:

() => Promise<void>

Triggered when the new task (+) button is clicked

() => Promise<void>

Triggered when the MCP Servers button is clicked

() => Promise<void>

Triggered when the History button is clicked

() => Promise<void>

Triggered when the Settings button is clicked

() => Promise<void>

Triggered when the Account button is clicked

() => Promise<void>

Triggered when the Worktrees button is clicked

() => Promise<void>

Triggered when the HAI Tasks button is clicked

Example:

import { sendChatButtonClickedEvent } from './core/controller/ui/subscribeToChatButtonClicked';

// Trigger the new task event
await sendChatButtonClickedEvent();

Webview Events

(preserveEditorFocus?: boolean) => void

Shows the HAI Build webview sidebarParameters:

preserveEditorFocus - When true, shows webview without forcing focus away from editor

(content: string) => Promise<void>

Adds content to the chat input fieldParameters:

content - The text to add to the input

Example:

import { sendAddToInputEvent } from './core/controller/ui/subscribeToAddToInput';

// Add terminal output to chat
await sendAddToInputEvent(`Terminal output:\n\`\`\`\n${terminalContents}\n\`\`\``);

State Management Events

Secret Storage Events

The extension listens for changes to secure credential storage: Event Handler:

context.secrets.onDidChange(async (event) => {
  if (event.key === 'cline:clineAccountId') {
    const secretValue = await context.secrets.get(event.key);
    if (secretValue) {
      // Login from another window - restore auth
      authService?.restoreRefreshTokenAndRetrieveAuthInfo();
    } else {
      // Logout - handle deauth
      authService?.handleDeauth(LogoutReason.CROSS_WINDOW_SYNC);
    }
  }
});

string

The key of the secret that changed (e.g., cline:clineAccountId)

Use cases:

Cross-window authentication sync
Credential updates
Logout propagation

Workspace Change Events

The extension tracks workspace folder changes for hook discovery: Event Handler:

vscode.workspace.onDidChangeWorkspaceFolders((callback) => {
  // Re-initialize hook discovery cache
  HookDiscoveryCache.getInstance().refresh();
});

File System Events

Hook Discovery Watcher

The extension watches for changes to hook files: File System Watcher:

const watcher = vscode.workspace.createFileSystemWatcher(
  new vscode.RelativePattern(dir, '*')
);

watcher.onDidCreate((uri) => {
  // Hook file created
});

watcher.onDidChange((uri) => {
  // Hook file modified
});

watcher.onDidDelete((uri) => {
  // Hook file deleted
});

Watched directories:

.clinerules/ - Local Cline rules
Custom hook directories

URI Handling Events

Deep Link Handler

The extension registers a URI handler for deep linking: Event Handler:

vscode.window.registerUriHandler({
  async handleUri(uri: vscode.Uri) {
    const url = decodeURIComponent(uri.toString());
    const isTaskUri = getUriPath(url) === TASK_URI_PATH;
    
    if (isTaskUri) {
      await openClineSidebarForTaskUri();
    }
    
    const success = await SharedUriHandler.handleUri(url);
    // Handle result
  }
});

vscode.Uri

The deep link URI that was opened (e.g., vscode://presidio-inc.hai-build-code-generator/task?id=123)

Supported URI paths:

/task - Open a specific task by ID

Telemetry Events

The extension tracks various user interactions for analytics:

Button Click Tracking

telemetryService.captureButtonClick(
  'command_focusChatInput',
  taskUlid?
);

string

Identifier for the button that was clicked

string

ULID of the current task (if applicable)

Slash Command Usage

telemetryService.captureSlashCommandUsed(
  taskUlid,
  commandName,
  commandType
);

string

ULID of the current task

string

Name of the slash command (e.g., ‘newtask’, ‘smol’, ‘my-workflow’)

'builtin' | 'mcp_prompt' | 'workflow'

Category of the slash command

Code Action Events

The extension provides code actions that appear in the editor:

Code Action Provider

Supported kinds:

vscode.CodeActionKind.QuickFix - Quick fixes for diagnostics
vscode.CodeActionKind.RefactorExtract - Extract refactoring (Explain)
vscode.CodeActionKind.RefactorRewrite - Rewrite refactoring (Improve)

Triggered when:

User right-clicks on code
User opens the quick fix menu (Ctrl/Cmd + .)
Diagnostics (errors/warnings) are present

Available actions:

CodeAction

Kind: QuickFixAdds selected code and diagnostics to chat

CodeAction

Kind: RefactorExtractRequests an explanation of the selected code

CodeAction

Kind: RefactorRewriteRequests AI suggestions to improve the code

CodeAction

Kind: QuickFix (preferred)Only appears when diagnostics are present. Attempts to fix errors/warnings.

Comment Thread Events

The extension provides a comment controller for AI code review:

Review Comment Controller

Controller ID: hai-ai-review Available commands:

Command

Replies to a comment threadWhen enabled: commentController == hai-ai-review && !commentIsEmpty

Command

Adds the comment thread to HAI Build chatWhen enabled: commentController == hai-ai-review

Development Mode Events

Development mode events are only available when IS_DEV === true

File Watcher for Hot Reload

In development mode, the extension watches for source file changes: Event Handler:

const watcher = vscode.workspace.createFileSystemWatcher(
  new vscode.RelativePattern(DEV_WORKSPACE_FOLDER, 'src/**/*')
);

watcher.onDidChange(({ scheme, path }) => {
  Logger.info(`${scheme} ${path} changed. Reloading VSCode...`);
  vscode.commands.executeCommand('workbench.action.reloadWindow');
});

Watched pattern: src/**/* in the development workspace folder Action: Automatically reloads VS Code window when source files change

Storage Migration Events

The extension performs storage migrations on activation: Migration functions:

() => void

Removes legacy API key storage

(context) => Promise<void>

Migrates custom instructions to global Cline rules (one-time)

(context) => Promise<void>

Migrates welcome view state based on existing API keys (one-time)

(context) => Promise<void>

Migrates workspace storage back to global storage (reverting previous migration)

(context) => Promise<void>

Ensures taskHistory.json exists and migrates legacy state (one-time)

(context) => Promise<void>

Cleans up MCP marketplace catalog from global state (moved to disk cache)

Hook Discovery Events

The extension uses a cache system for performance optimization: Cache initialization:

HookDiscoveryCache.getInstance().initialize(
  context,
  createWatcher,
  onWorkspaceFoldersChanged
);

Events:

File creation in hook directories
File changes in hook directories
File deletion in hook directories
Workspace folder changes

Custom Event Integration

To integrate with HAI Build events in your own extension:

Listen to Extension Activation

const haiExtension = vscode.extensions.getExtension(
  'presidio-inc.hai-build-code-generator'
);

if (haiExtension) {
  // Extension is installed
  if (haiExtension.isActive) {
    // Already activated
    const api = haiExtension.exports;
  } else {
    // Wait for activation
    const api = await haiExtension.activate();
  }
}

Trigger HAI Build Commands

// Open HAI Build and add content to chat
await vscode.commands.executeCommand('hai.focusChatInput');
await vscode.commands.executeCommand('hai.addToChat', range, diagnostics);

Access the Controller API

const api = haiExtension.exports;
const controller = api.controller;

// Use controller methods
await controller.clearTask();
await controller.postStateToWebview();

Best Practices

Check extension availability

Always verify the HAI Build extension is installed and activated before attempting to use its API:

const extension = vscode.extensions.getExtension('presidio-inc.hai-build-code-generator');
if (!extension) {
  vscode.window.showErrorMessage('HAI Build extension not found');
  return;
}

Handle activation failures

Extension activation might fail. Always handle errors:

try {
  const api = await extension.activate();
} catch (error) {
  Logger.error('Failed to activate HAI Build:', error);
}

Dispose event listeners

When registering event listeners, always add them to your extension’s subscriptions:

const disposable = vscode.workspace.onDidChangeConfiguration((e) => {
  // Handle config change
});
context.subscriptions.push(disposable);

Use telemetry responsibly

If you’re integrating with HAI Build’s telemetry, ensure you:

Follow privacy guidelines
Respect user’s telemetry settings
Only track meaningful interactions

Commands

Complete VS Code commands reference

Slash Commands

In-chat slash commands

Extension API

CLI Reference

LLM Providers

Overview

Extension Lifecycle Events

Extension Activation

Extension Deactivation

User Interaction Events

Button Click Events

Webview Events

State Management Events

Secret Storage Events

Workspace Change Events

File System Events

Hook Discovery Watcher

URI Handling Events

Deep Link Handler

Telemetry Events

Button Click Tracking

Slash Command Usage

Code Action Events

Code Action Provider

Comment Thread Events

Review Comment Controller

Development Mode Events

File Watcher for Hot Reload

Storage Migration Events

Hook Discovery Events

Custom Event Integration

Listen to Extension Activation

Trigger HAI Build Commands

Access the Controller API

Best Practices

See Also

Commands

Slash Commands

​Overview

​Extension Lifecycle Events

​Extension Activation

​Extension Deactivation

​User Interaction Events

​Button Click Events

​Webview Events

​State Management Events

​Secret Storage Events

​Workspace Change Events

​File System Events

​Hook Discovery Watcher

​URI Handling Events

​Deep Link Handler

​Telemetry Events

​Button Click Tracking

​Slash Command Usage

​Code Action Events

​Code Action Provider

​Comment Thread Events

​Review Comment Controller

​Development Mode Events

​File Watcher for Hot Reload

​Storage Migration Events

​Hook Discovery Events

​Custom Event Integration

​Listen to Extension Activation

​Trigger HAI Build Commands

​Access the Controller API

​Best Practices

​See Also

Commands

Slash Commands

Overview

Extension Lifecycle Events

Extension Activation

Extension Deactivation

User Interaction Events

Button Click Events

Webview Events

State Management Events

Secret Storage Events

Workspace Change Events

File System Events

Hook Discovery Watcher

URI Handling Events

Deep Link Handler

Telemetry Events

Button Click Tracking

Slash Command Usage

Code Action Events

Code Action Provider

Comment Thread Events

Review Comment Controller

Development Mode Events

File Watcher for Hot Reload

Storage Migration Events

Hook Discovery Events

Custom Event Integration

Listen to Extension Activation

Trigger HAI Build Commands

Access the Controller API

Best Practices

See Also