windsurf-hello-world

Devin Desktop Hello World

Overview

Devin Desktop is the current name for Windsurf. This walkthrough exercises Cascade Code and Chat modes, Supercomplete, and inline Command editing with a disposable example.

Prerequisites

• Completed windsurf-install-auth setup
• Devin Desktop open with a disposable or version-controlled project folder

Tool Use

• Use Read to inspect only the repository files and configuration needed for the request.
• Use Write only for a new artifact the user requested; never write credentials or unreviewed production configuration.
• Use Edit for bounded, reviewable changes and preserve unrelated user work.

Instructions

Step 1: Experience Supercomplete (Tab Completions)

Open any code file and start typing. Supercomplete predicts your intent based on recent edits, cursor movement, and surrounding context.

// Type this in a new file: hello.ts
// After typing "function greet", Supercomplete suggests the rest

function greet(name: string): string {
  // Just type "return" and press Tab -- Supercomplete fills the template literal
  return `Hello, ${name}! Welcome to Windsurf.`;
}

// Start typing "const users" -- Supercomplete predicts array based on greet() context
const users = ["Alice", "Bob", "Charlie"];
users.forEach(user => console.log(greet(user)));

Key Supercomplete behaviors:

• Press Tab to accept a suggestion
• Press Esc to dismiss
• Suggestions appear as gray ghost text
• Uses recent editor activity and surrounding context for intent prediction

Step 2: Use Cascade Code Mode

Open Cascade and select Code mode. Use the visible command or current keybinding because imported editor profiles can change shortcuts.

Prompt to try:
"Create a REST API endpoint in src/api.ts using Express that serves
the greet function. Include error handling for missing name parameter."

Cascade will:

1. Create src/api.ts with Express setup
2. Import the greet function
3. Add error handling
4. Show diffs for your review

Review and accept/reject each file change before Cascade proceeds.

Step 3: Use Cascade Chat Mode

Switch to Chat mode (toggle in Cascade panel) for questions that don't need file edits:

Prompt: "Explain the difference between Code and Chat mode in Cascade"

Expected response: Code mode can create/modify files and run terminal commands.
Chat mode answers questions without touching your codebase.

Step 4: Try Inline Command (Cmd/Ctrl+I)

Highlight a block of code in the editor and press Cmd/Ctrl+I to invoke Command mode:

Select the greet function, then type:
"Add JSDoc documentation and input validation"

Cascade edits the selected code inline and presents a diff for explicit acceptance or rejection.

Step 5: Use @ Context Mentions

In Cascade chat, use @ to inject specific context:

@src/api.ts -- reference a specific file
@src/       -- reference an entire directory
@web        -- search the web for current info

Example prompt with context:

"@src/api.ts Add rate limiting middleware to all endpoints"

Output

• Working Supercomplete experience with Tab completions
• Cascade Code mode: file creation and modification
• Cascade Chat mode: codebase questions without edits
• Inline Command mode: targeted code editing
• @ context mentions for precise AI context

Error Handling

Examples

Terminal Command Mode

Press Cmd/Ctrl+I in the terminal, then type:
"Find all TypeScript files that import express"

Windsurf generates: find src -name "*.ts" -exec grep -l "express" {} \;

Preview Your App

Ask Cascade: "Preview the API server in the browser"
Windsurf opens an in-IDE preview tab with your running app.
Click elements in the preview to send them back to Cascade for edits.

Resources

• Focused first-party references
• Windsurf Getting Started
• Cascade Overview
• Autocomplete Tips

Related Skill

Continue with windsurf-local-dev-loop to turn this disposable exercise into a repeatable, test-gated development workflow for a real repository.