Publish preview
In the Dev module, the Preview tab can share your local development server on the Internet with a temporary public link (*.trycloudflare.com). Useful for demos, checking a site on a phone, or showing work to someone else - not production hosting.
No Cloudflare account is required. Navin starts the tunnel helper for you from the Preview toolbar.
Auto-open Preview
When the agent scaffolds or starts a web app, Preview often opens by itself once the local server is ready. For Android, the Mobile tab can open the same way after a device preview starts. Publish (the public link) always stays a manual click.
On a narrow screen, the Dev chat becomes a bottom sheet so Preview can use the full width; auto-open can also collapse the chat so the app stays in focus.
Usage
- Start your project’s local preview (ask the agent, or use a terminal in the workbench if you prefer).
- Open Preview (it may already be open) and confirm the local address shown there (for example a
127.0.0.1URL with a port). - Click Publish next to Open.
- Wait for the public
https://….trycloudflare.comlink to appear: copy it, open it, or Stop when you are done.
Navin picks the port from the local Preview URL and keeps the tunnel pointed at that address on your machine.
Requirements: Internet access. Publishing works from the same computer that is running Navin. On first use, Navin may download the tunnel helper automatically.
What it is not
| Expectation | Reality |
|---|---|
| Permanent production hosting | No - temporary tunnel to your machine |
Custom domain mysite.com | No - random *.trycloudflare.com URL |
| Cloudflare account required | No |
Do I need a Cloudflare account?
| Goal | Cloudflare account? |
|---|---|
| Quick share via Publish | No |
| Your own domain / subdomain | Yes - outside this simple Publish flow |
Troubleshooting
| Message or symptom | Likely cause | Hint |
|---|---|---|
| Host not allowed in the local app | Stale tunnel state | Stop, then Publish again |
| Could not download the tunnel helper | Network blocked | Check Internet, or install the helper so Navin can find it |
| Nothing listening on that port | Dev server not running | Start the local preview, then Publish again |
| Need a URL with a port | Local address incomplete | Use a full local URL with an explicit port in Preview |
| Publish only on this machine | Trying from another device’s Navin | Publish from the computer that runs the project |
Related
- Workbench - Preview / Browser panel