In your stack
One review link per preview deployment
Every branch you push to Vercel gets its own URL. Paste that URL into Writhink and you get a second link — one your client opens with no account and pins comments on. Feedback lands on the branch that caused it, not in a pile of notes about "the site".
No credit card. Your client doesn’t need an account.
01
The half that is still broken
Vercel already solved the hard part. The branch is deployed, it has a URL, and it is exactly the code in the pull request. What is still broken is the response. You paste the preview link into an email and back comes "the hero feels off on mobile", with no way to tell which hero, which breakpoint, or which element they were actually looking at.
Writhink takes that preview URL and gives you a review link for it. Your client clicks the element and types the sentence. You get the element, the route, the viewport size, the device type and a screenshot of the pinned spot, attached to the comment. The guessing step disappears, and so does the round trip where you ask for a screenshot and get a photo of a monitor.
02
Wiring a review to a branch
About four seconds of copying. There is nothing to configure on the Vercel side, and nothing to install on your client's side.
- Step 1
Push the branch
Vercel builds the preview as it always does. You do not change your pipeline, your project settings, or your build command.
- Step 2
Copy the right address
Vercel gives you two, and the difference decides whether the review link stays useful after your next commit. The table below is that decision.
- Step 3
Create the Writhink project and share the link
One link out. No seat on your Vercel team, no signup, no app. The reviewer types a display name and starts pinning.
- Step 4
Read the pins next to the diff
Each comment carries the page and the element it was left on, so you can match it to the component in the branch rather than hunting for what they meant.
- Step 5
Generate the prompt and push to the same branch
Writhink rewrites the comments clearly, merges duplicates, groups them by page and element, and hands you one prompt for your coding agent. You push; your client refreshes the same review link and checks the same items.
03
The two Vercel-specific decisions
Everything else about getting a page into review — when a shared link works, when you need the Chrome extension, when the embeddable widget is the better idea — follows the general rule on /website-feedback-tool. These two belong to Vercel.
| The decision | What to do | What happens if you get it wrong |
|---|---|---|
| Which preview URL to paste | The branch alias — project-git-branch-team.vercel.app — not the per-deployment URL | A per-deployment URL is frozen to one commit. It keeps resolving after you push a fix, so your client re-opens the review link, sees the build they already complained about, and repeats themselves — worse than a dead link, because nothing looks wrong. The branch alias always serves the latest deployment for that branch, so the same review link keeps pace with your pushes. When a fix removes the element a pin was sitting on, the screenshot stored with that comment is the record of what it was about. |
| Deployment Protection is on | Chrome extension, or turn protection off for that one branch while the review runs | The Writhink proxy arrives as a stranger and gets the Vercel Authentication screen, so the review link shows a login instead of your build. The extension works because your browser is already through it — but then every reviewer needs Chrome, the extension, and their own access to the preview. That suits your own team and technical clients; it is a lot to ask of a client's marketing director. The same trade-off applies to anything behind your app's own login. |
The extension is Chrome only: no Firefox, Safari, or Edge build.
04
What you get back for a branch
Everything below is stored per comment, so a review of a preview is a complete record of what was asked for on that build:
- The page URL and the element anchor, so a comment survives the content above it changing.
- Viewport size and device type — desktop, tablet or mobile. Not the operating system, not the browser, not the handset model; Writhink does not collect those.
- An automatic screenshot of the pinned area at the moment the comment was left.
- Attachments from the reviewer — up to five files, 10 MB each.
- Four statuses (open, in progress, in review, resolved) and public replies, so sign-off happens on the item.
- One generated prompt for the whole branch, with items that are still ambiguous flagged as unclear rather than guessed at.
05
Let Claude Code work from the branch feedback
Writhink runs a remote MCP server at mcp.writhink.com. Any MCP-capable client connects to it — Claude Code, Cursor, Claude Desktop. In Claude Code the connect command is claude mcp add --transport http writhink https://mcp.writhink.com/mcp, and it signs you in over OAuth 2.1 in the browser the first time a tool runs.
In branch terms, that lets the agent pull everything left on the preview with its page, element, viewport and screenshot context intact, work down the list against the code already open in front of you, mark an item in review the moment the branch redeploys, and post the answer the reviewer reads on their own pin — without you switching off the branch to go and type it somewhere. Two things to hold on to: the server never sees your repository, and the agent reads one active organization at a time. The seven tools and the authorization model are set out on /visual-feedback-for-ai-agents.
06
There is no Vercel integration
Writhink is not in the Vercel Marketplace. There is no GitHub check, no comment posted on your pull request, no project created automatically per branch, and no environment variable to set. Writhink never talks to your Vercel account and cannot see your deployments or your team. Everything on this page is you copying a URL — which is why it works identically on Netlify, Cloudflare Pages, Render, or a box you rent.
One consequence worth planning for: the review link points at a URL you control, so if you delete the branch, the deployment behind it stops resolving. The comments, the screenshots and the generated prompt stay in Writhink, but the live page they refer to is gone. Generate the prompt and download the .md before you clean up the branch.
The same goes the other way. Nothing in Writhink knows a deployment was promoted to production, so a project pointed at a branch alias keeps reviewing that branch forever. When the work ships, point a project at the production URL and let the branch project close out with its items resolved — that history is the record of what the branch was asked to do.
Before you count on it
Writhink is in open beta: everything described here is available and free, no credit card. Paid plans are announced but not purchasable yet. The one limit that applies today is five AI prompt generations a month per organization.
FAQ
Questions people actually ask
- Is there a Writhink integration for Vercel?
- No. There is no Marketplace listing, no GitHub check, no PR comment, and no connection to your Vercel account. You copy a preview URL into Writhink and share the review link it gives you. Nothing about your deployment pipeline changes.
- My preview is behind Vercel Authentication. Can a client still review it?
- Not through a shared link — the Writhink proxy hits the same auth screen a stranger would. Either use the Chrome extension, which reviews the page in your own already-authenticated browser, or make that specific branch reachable without protection for the length of the review.
- Does the review link break when I push a new commit?
- It depends which address you used. A per-deployment URL is frozen to that commit, so the review keeps showing the old build. The stable branch alias always serves the latest deployment for the branch, so use that and the same review link keeps pace with your pushes.
- Should production and a preview be one project or two?
- Two. Keeping the branch review separate from production feedback is what lets you say "these twelve items block the merge" without sorting them out of everything else. Creating a project is a paste and a name.
- Can the client see the review on their phone?
- Yes, and you should ask them to. It is a link in a browser, with no app and no account, and Writhink records the viewport size and the device type with each pin — so a mobile complaint arrives with the width that produced it.
- We deploy on Netlify or Cloudflare Pages. Does any of this change?
- No. Writhink only ever sees a URL, so a Netlify deploy preview, a Cloudflare Pages branch preview or a staging box behave exactly like a Vercel preview. The two decisions are the same everywhere: paste the address that follows the branch rather than one frozen to a commit, and work out whether a proxy can reach it without a password.
Start
Send one link. Get feedback you can build from.
Your clients comment right on the page — no account, no screenshots, no voice notes. Writhink sorts the comments and writes the prompt for your AI.