Windsurf IDE Guide: Cascade AI Agent for Developers

Windsurf is an AI-first IDE developed by Codeium that launched in late 2024 and quickly gained a dedicated following among developers who wanted something beyond simple autocomplete. Its flagship feature, the Cascade AI agent, can plan and execute multi-step coding tasks across your entire codebase — not just the file you’re looking at. This guide covers installation, core features, practical usage, and how it stacks up against the competition.

What Makes Windsurf Different?

Most AI coding tools bolt AI onto an existing editor. Windsurf was designed from the ground up with AI as a first-class citizen. The key distinction is Cascade, which operates in two modes:

Write mode: Cascade can autonomously create files, edit multiple files simultaneously, run terminal commands, and iterate based on test results
Chat mode: A conversational interface for asking questions, explaining code, or getting suggestions without automatic execution

This “agentic flow” — where the AI takes sequences of actions rather than just completing a single prompt — is what differentiates Windsurf from simpler tools.

Installation

Windsurf is available for Windows, macOS, and Linux.

Download and Install

Go to codeium.com/windsurf and download the installer for your OS
Run the installer — it sets itself up like any standard desktop app
On first launch, sign in with a Codeium account (free tier available)
Import your VS Code settings and extensions optionally — Windsurf is VS Code-based and supports most VS Code extensions

# On macOS with Homebrew (if available):
brew install --cask windsurf

# Or download directly from the site for Windows/Linux

Setting Up Your Environment

After installation:

Open a project folder or workspace as you would in VS Code
Your existing VS Code extensions, themes, and keybindings transfer over
Click the Cascade icon in the sidebar (or press Cmd+L / Ctrl+L) to open the AI panel

The Cascade AI Agent

Cascade is the heart of Windsurf. Here’s how to use it effectively.

Starting a Cascade Session

Open the Cascade panel and type a task in natural language. Be specific about what you want accomplished:

Build a REST API endpoint in Express that accepts a POST request at /api/users, 
validates the request body (name, email required), saves to a MongoDB collection, 
and returns the created user. Add proper error handling.

Cascade will:

Analyze your existing project structure
Plan the steps needed
Create or modify files
Show you diffs before applying changes (configurable)
Run the code to verify it works

Multi-File Edits

One of Cascade’s strongest features is coordinated multi-file changes. For example:

Rename the UserService class to AccountService and update all imports, 
references, and test files throughout the project.

Cascade understands your project’s import graph and makes consistent changes across all affected files simultaneously — a task that’s tedious and error-prone to do manually.

Terminal Integration

In Write mode, Cascade can run terminal commands as part of its workflow:

Install the missing dependencies, run the test suite, and fix any failing tests.

Cascade will run npm install, execute npm test, read the output, identify failures, edit the source code, and re-run tests — all automatically.

Inline Chat

For quick, in-context help without switching to the Cascade panel, use inline chat:

Select code and press Cmd+I (macOS) or Ctrl+I (Windows/Linux)
Type a quick instruction: “Optimize this function for readability” or “Add JSDoc comments”
The suggestion appears inline as a diff you can accept or reject

Model Selection

Windsurf lets you choose which underlying AI model Cascade uses. Available options include Claude Sonnet/Opus models, GPT-4o, and Codeium’s own models. This is a significant advantage — you’re not locked into one provider’s intelligence.

Model	Best For
Claude Sonnet 4	Complex refactoring, long context
GPT-4o	General coding tasks
Codeium Base	Fast autocomplete, low latency

Free vs Paid Tiers

Feature	Free	Pro ($15/mo)	Teams
Autocomplete	Unlimited	Unlimited	Unlimited
Cascade queries	25/month	500/month	Unlimited
Premium models	Limited	Full access	Full access
Fast response	No	Yes	Yes

The free tier is genuinely useful for learning the tool. For daily professional use, the 25 Cascade queries/month limit pushes most developers to Pro.

Windsurf vs Cursor vs VS Code Copilot

Feature	Windsurf	Cursor	VS Code + Copilot
Agentic (multi-step)	Yes (Cascade)	Yes (Composer)	Limited
Multi-file edits	Yes	Yes	Limited
Terminal integration	Yes	Yes	No
Model choice	Yes	Yes	GPT-4o only
Base editor	VS Code fork	VS Code fork	VS Code native
Free tier	25 Cascade/mo	2-week trial	Copilot free limited
Paid price	$15/mo	$20/mo	$10/mo
Codebase indexing	Yes	Yes	Limited

Cursor is Windsurf’s closest competitor. Both are VS Code forks with agentic AI. The differences are nuanced:

Windsurf’s Cascade tends to be more autonomous and “agent-like”
Cursor’s Composer is more incremental and shows changes step by step
Cursor has a slightly larger community and more third-party resources
Windsurf’s free tier is more generous for casual exploration

VS Code + GitHub Copilot is best if you’re deeply invested in the VS Code ecosystem and extensions, and don’t need agentic capabilities. For the $10/month price point, it’s solid but falls behind on complex multi-file tasks.

Tips for Getting the Most out of Windsurf

Be Specific in Cascade Prompts

Vague: “Make the login better” Better: “Add rate limiting to the login endpoint — max 5 attempts per IP per 15 minutes using Redis. Use the existing express-rate-limit package if it’s already installed.”

Use the Explain Feature

Select any code block and ask Cascade to explain it. This is invaluable when onboarding to a new codebase:

Explain what this middleware chain does and identify any potential security issues.

Set a CLAUDE.md or Rules File

Windsurf reads a .windsurfrules file in your project root that sets persistent instructions for Cascade:

Always use TypeScript strict mode.
Prefer async/await over Promise chains.
Write Jest tests for all new functions.
Follow the existing naming conventions in this project.

Use Checkpoint Reviews

Before accepting Cascade’s changes in Write mode, review the diff carefully. Cascade is powerful but not infallible — it occasionally makes assumptions about your architecture that need correction.

Verdict

Windsurf is one of the most capable AI coding environments available today. If you’re doing serious software development and want an AI that can take a complex task and actually execute it across your codebase, Cascade is genuinely impressive. The free tier lets you evaluate it before committing, and the $15/month Pro plan is competitive for what you get.