Google Apps Script clasp: Develop Locally with VS Code

The online Apps Script editor is fine for quick scripts, but for anything serious you want a real editor, git version control, and a proper development workflow. clasp is Google's official CLI that lets you develop Apps Script locally and push changes to Google.

Install clasp

You need Node.js installed. Then:

npm install -g @google/clasp

Log in to your Google account

clasp login

This opens a browser window to authorise clasp with your Google account.

Create a new project

# Create a new standalone script
clasp create --title "My Script" --type standalone

# Or create a script bound to a Sheet (pass the spreadsheet ID)
clasp create --title "My Sheet Script" --parentId "YOUR_SPREADSHEET_ID" --type sheets

This creates a .clasp.json file in your directory linking it to the Apps Script project.

Clone an existing project

clasp clone "YOUR_SCRIPT_ID"

Find the script ID in the Apps Script editor under Project Settings.

Push and pull code

# Push local changes to Apps Script
clasp push

# Pull latest code from Apps Script to local
clasp pull

Open the script in the browser

clasp open

Watch for changes and auto-push

clasp push --watch

This keeps watching your local files and pushes every time you save — great during active development.

TypeScript support

clasp has built-in TypeScript support. Rename your files from .js to .ts and clasp will compile them before pushing.

Install the Apps Script type definitions for full autocomplete:

npm install --save-dev @types/google-apps-script

Now your editor knows about SpreadsheetApp, GmailApp, DriveApp, and all other services — with full type checking.

function sendEmail(recipient: string, subject: string, body: string): void {
  GmailApp.sendEmail(recipient, subject, body);
}

function getSheetData(): string[][] {
  const sheet: GoogleAppsScript.Spreadsheet.Sheet =
    SpreadsheetApp.getActiveSpreadsheet().getActiveSheet();
  return sheet.getDataRange().getValues();
}

Project structure example

A typical clasp project looks like this:

my-script/
├── .clasp.json       ← Links to your Apps Script project
├── .claspignore      ← Files to exclude from push (like node_modules)
├── appsscript.json   ← Script manifest (scopes, timezone, etc.)
├── src/
│   ├── main.ts
│   ├── utils.ts
│   └── config.ts
├── package.json
└── tsconfig.json

.claspignore

Keep local files out of your Apps Script project:

node_modules/**
.git/**
*.md
package.json
tsconfig.json

Manage versions and deployments

# Create a new versioned snapshot
clasp version "v1.0 - initial release"

# List all versions
clasp versions

# Deploy a version as a Web App or API Executable
clasp deploy --versionNumber 1 --description "Production"

# List deployments
clasp deployments

Tips

Add .clasp.json to .gitignore if you're sharing the repo — it contains your script ID.
Use appsscript.json to pin OAuth scopes explicitly so you're not surprised by permission prompts.
clasp supports multiple environments by maintaining separate .clasp.json files for dev and prod script IDs.
Run clasp logs to stream Stackdriver logs from your deployed script directly in the terminal.