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Cosine

Instant Sites

The Instant Sites feature lets you publish any static folder or file in your project to a live URL—instantly, on demand. You can deploy via your editor’s file tree or by asking Cosine directly. This guide covers enabling the feature, both deployment methods, customizing your subdomain, using a custom 404 page, and how to manage your deployments.

Table of Contents

Section titled “Table of Contents”
  1. Enabling Instant Sites
  2. Deployment Methods
    • A. Right-Click Deploy
    • B. “Ask Cosine” Deploy
  3. Viewing & Sharing Your Deployment
  4. Customizing the Subdomain
  5. Custom 404 Pages
  6. Troubleshooting & FAQs

1. Enabling Instant Sites

Section titled “1. Enabling Instant Sites”
  1. Open your project’s Dashboard.
  2. Navigate to Settings → Deployment Settings.
  3. Toggle Instant Sites to On.

Once enabled, “Deploy” options and Cosine’s deploy tool become available in your editor.

2. Deployment Methods

Section titled “2. Deployment Methods”

A. Right-Click Deploy

Section titled “A. Right-Click Deploy”
  1. In your IDE’s File Tree, locate the folder (e.g. public/, docs/) or single file (index.html) you want to publish.
  2. Right-click it and select Deploy.

You’ll see a notification when it’s live.

B. “Ask Cosine” Deploy

Section titled “B. “Ask Cosine” Deploy”

  1. Open the Cosine Chat or Command Palette in your editor (e.g. via the Cosine icon or Ctrl/Cmd+Shift+P).

  2. Type a natural-language request, for example:

    Deploy the folder docs/ as an instant site

  3. Choose the path from the suggestions, confirm any prompt (e.g. name or description), and send.

Cosine will run the deployment and notify you when the site is published.

3. Viewing & Sharing Your Deployment

Section titled “3. Viewing & Sharing Your Deployment”

  • Live URL
    Once deployed, Instant Sites assigns a URL like:

    https://<random-id>.cosine.page

  • Share Deployment Modal
    In the preview panel or after the deploy notification, click Share to open the modal:

    • Copy URL button copies the live link.
    • Custom Subdomain input lets you update the subdomain in place.

4. Customizing the Subdomain

Section titled “4. Customizing the Subdomain”
  1. Open the Share Deployment modal (from preview panel or post-deploy alert).
  2. Under Custom Subdomain, enter your desired prefix (e.g. my-docs).
  3. Click Update Subdomain.

Your site moves to:

https://my-docs.cosine.page

5. Custom 404 Pages

Section titled “5. Custom 404 Pages”

If your static folder contains a 404.html file at its root, Instant Sites will serve that as the custom “Not Found” page. Otherwise, a default 404 page is shown.

  • To use a custom 404:
    1. Add a file named 404.html to the root of the folder you’re deploying.
    2. Deploy or redeploy that folder.
    3. Visit a non-existent path (e.g. https://<id>.cosine.page/nonexistent) to see your custom 404 page in action.

6. Troubleshooting & FAQs

Section titled “6. Troubleshooting & FAQs”

Q: I don’t see Deploy in my file tree.

  • Ensure Instant Sites is toggled on in Settings → Deployment and restart your editor.

Q: Cosine didn’t pick the correct folder.

  • Be explicit in your prompt:

    Deploy the public/ directory

Q: My custom 404 isn’t showing.

  • Confirm your 404.html is in the root of the deployed folder and that you redeployed after adding it.

Q: Custom subdomain update failed.

  • Remember, subdomains under cosine.page must be unique.
  • If you see an error, try a different prefix that isn’t already in use.

Q: My site shows 404 after deploy.

  • Confirm the target folder/file contains an index.html.
  • Review the deployment logs in the Preview panel for errors.

You’re all set! 🚀
Enable Instant Sites, deploy in one click or with a quick Cosine prompt - instantly on cosine.page. Enjoy!