How to use GS Copilot.
A practical guide to getting the most out of your AI coding assistant: installation, the four features that matter, and the habits of power users.
Install, sign in, ship in 90 seconds.
Two steps. No config files. No CLI. Your existing Google account does the heavy lifting.
Installation & Setup
Install the GS Copilot extension from the Chrome Web Store and sign in with the same Google account you use for Apps Script.
- Open the Chrome Web Store listing and add GS Copilot to Chrome.
- Sign in with the Google account that owns your Apps Script projects.
- Open script.google.com and refresh the editor once after installing.
- Use the Google account that owns your Apps Script projects
- Grant the requested permissions so the IDE panel can mount
- Pin the extension to the toolbar to confirm it loaded
First Project Setup
Open any Apps Script project (or create one). Copilot mounts a side panel inside the IDE the moment the project loads.
- Open an existing Apps Script project or create a blank one.
- Wait for the Copilot panel to appear inside the editor.
- Ask a small first question, such as explaining the active file.
- Start with a small project to see how context loads
- Keep file names descriptive — Copilot uses them for grounding
- Save often while experimenting; Apps Script keeps versions for you
The four things you'll use every day.
Master these and you've mastered Copilot. Each workflow is explained in plain steps so you can try it immediately.
Chat Mode
Use the side panel to ask questions, debug errors, and request changes with project context already attached.
- Open the Copilot panel beside your code.
- Describe the outcome you want in one or two sentences.
- Review the answer, then ask a follow-up or apply the suggested change.
- Be specific about what you want to change
- Reference function names instead of pasting code
- Use follow-ups; Copilot remembers the thread
Inline Suggestions
Get ghost-text suggestions while you type, then accept only the parts that help.
- Place your cursor where the next code should go.
- Pause briefly so Copilot can read the surrounding context.
- Press Tab to accept or Esc to dismiss the suggestion.
- Keep your cursor at the end of the line for best context
- Write a short comment first when the next step is complex
- Reject suggestions freely when they do not match your intent
Multi-File Context
Attach the files that matter so Copilot understands triggers, helpers, libraries, and connected services.
- Open the context picker in the panel.
- Add the files involved in the task you are working on.
- Remove files that no longer matter before asking the next question.
- Include only the files the task actually touches
- Keep file names descriptive for better grounding
- Pin important files when you want them kept across the session
Chat History & Branches
Return to saved project conversations or branch from an earlier message when you want to try a different fix.
- Open chat history from the Copilot panel.
- Select the conversation that matches the project or bug.
- Fork from an older message before testing a different approach.
- Name important threads so they are easier to find
- Fork before trying risky changes
- Reuse a successful thread on similar bugs
Ship faster without shipping bugs.
How experienced users get the most out of Copilot while keeping their code reviewable.
Effective Prompting
Give Copilot the goal, the constraints, and the exact service you are using.
- Start with the outcome you want.
- Add the current error, file, function, or data shape.
- Ask for code plus a short explanation when the change is important.
- Lead with the outcome, not the implementation
- Mention error messages verbatim when debugging
- Specify the service: SpreadsheetApp, DriveApp, or GmailApp
- Ask for explanations alongside the code
Code Quality & Security
Treat AI output like a teammate's draft: useful, fast, and worth reviewing before it ships.
- Read the generated code before applying it.
- Run the smallest safe test you can.
- Move secrets into PropertiesService instead of prompts or source code.
- Test on a copy of the sheet first
- Validate every external input from forms or URL params
- Keep changes small enough to review
- Never paste secrets into a prompt