Windsurf Extension Development & Events

Overview

Windsurf is built on VS Code and supports the full VS Code Extension API. Build custom extensions to track workspace events, integrate with external tools, and extend Cascade's capabilities. This skill covers extension development specific to the Windsurf environment.

Prerequisites

• Node.js 18+ and npm
• VS Code Extension API familiarity
• yo and generator-code for scaffolding
• Windsurf IDE for testing

Instructions

Step 1: Scaffold Extension

# Install scaffolding tools
npm install -g yo generator-code

# Generate extension
yo code
# Select: New Extension (TypeScript)
# Name: my-windsurf-extension

Step 2: Track Workspace Events

// src/extension.ts
import * as vscode from "vscode";

export function activate(context: vscode.ExtensionContext) {
  console.log("Extension active in Windsurf");

  // Track file saves
  const saveListener = vscode.workspace.onDidSaveTextDocument(
    async (document) => {
      const diagnostics = vscode.languages.getDiagnostics(document.uri);
      const errors = diagnostics.filter(
        (d) => d.severity === vscode.DiagnosticSeverity.Error
      );
      if (errors.length > 0) {
        vscode.window.showWarningMessage(
          `${document.fileName}: ${errors.length} error(s) after save`
        );
      }
    }
  );

  // Track active editor changes
  const editorListener = vscode.window.onDidChangeActiveTextEditor(
    (editor) => {
      if (editor) {
        const lang = editor.document.languageId;
        const lines = editor.document.lineCount;
        console.log(`Opened: ${editor.document.fileName} (${lang}, ${lines} lines)`);
      }
    }
  );

  // Track terminal output
  const terminalListener = vscode.window.onDidWriteTerminalData((event) => {
    // Can monitor for specific patterns (errors, warnings)
    if (event.data.includes("ERROR") || event.data.includes("FAIL")) {
      vscode.window.showWarningMessage("Error detected in terminal output");
    }
  });

  context.subscriptions.push(saveListener, editorListener, terminalListener);
}

Step 3: Send Events to External System

// src/webhook.ts
import * as vscode from "vscode";

interface WorkspaceEvent {
  event: string;
  file?: string;
  language?: string;
  timestamp: string;
  metadata?: Record<string, unknown>;
}

async function sendEvent(event: WorkspaceEvent): Promise<void> {
  const webhookUrl = vscode.workspace
    .getConfiguration("windsurf-events")
    .get<string>("webhookUrl");

  if (!webhookUrl) return;

  try {
    await fetch(webhookUrl, {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify(event),
    });
  } catch (err) {
    console.warn("Webhook delivery failed:", err);
  }
}

// Debounce frequent events
const debounceMap = new Map<string, NodeJS.Timeout>();

function debouncedSend(event: WorkspaceEvent, delayMs = 2000): void {
  const key = `${event.event}:${event.file}`;
  clearTimeout(debounceMap.get(key));
  debounceMap.set(
    key,
    setTimeout(() => {
      sendEvent(event);
      debounceMap.delete(key);
    }, delayMs)
  );
}

Step 4: Extension package.json

{
  "name": "windsurf-events",
  "displayName": "Windsurf Events",
  "version": "1.0.0",
  "engines": { "vscode": "^1.85.0" },
  "activationEvents": ["onStartupFinished"],
  "main": "./dist/extension.js",
  "contributes": {
    "configuration": {
      "title": "Windsurf Events",
      "properties": {
        "windsurf-events.webhookUrl": {
          "type": "string",
          "description": "URL to send workspace events to"
        },
        "windsurf-events.trackSaves": {
          "type": "boolean",
          "default": true,
          "description": "Track file save events"
        },
        "windsurf-events.trackErrors": {
          "type": "boolean",
          "default": true,
          "description": "Track terminal error events"
        }
      }
    },
    "commands": [
      {
        "command": "windsurf-events.showStatus",
        "title": "Windsurf Events: Show Status"
      }
    ]
  }
}

Step 5: Build and Install

# Build
npm run compile
# or: npm run build

# Package as .vsix
npx vsce package

# Install in Windsurf
windsurf --install-extension windsurf-events-1.0.0.vsix

# Or publish to marketplace
npx vsce publish

Step 6: Test in Windsurf

1. Open Extension Development Host: F5 in Windsurf
2. A new Windsurf window opens with extension loaded
3. Open a file, save it, trigger events
4. Check Output panel > "Windsurf Events" channel
5. Verify webhook delivery (use https://webhook.site for testing)

Error Handling

Examples

Team Analytics Extension

// Track AI acceptance rate per developer
vscode.languages.registerInlineCompletionItemProvider(
  { pattern: "**" },
  {
    provideInlineCompletionItems(document, position) {
      // Log completion requests (don't interfere with Supercomplete)
      console.log(`Completion at ${document.fileName}:${position.line}`);
      return []; // Return empty -- let Windsurf handle completions
    }
  }
);

Quick Test Webhook

# Start a test webhook receiver
npx -y webhook-relay -p 3456
# Configure extension: windsurf-events.webhookUrl = "http://localhost:3456"

Resources

• VS Code Extension API
• VS Code Extension Publishing
• Windsurf Marketplace

Next Steps

For multi-environment setup, see windsurf-multi-env-setup.