TweakThis by TweakThis

Your clients report, your agent fixes.

TweakThis is for anyone who looks after several websites, their clients' or their own. A client points at what should change on their site and writes a note; Claude Code or Codex fetches it over MCP, fixes your code and reports back for sign-off. Or you fix it by hand.

How it works
- Open TweakThis on a page of one of your projects and pick an element, or draw a region.
- Write what should change. TweakThis attaches the context a developer would otherwise ask for: the page address and title, the element's selectors, HTML and styles, the viewport, and a screenshot of the visible page.
- Card details, one-time codes and passwords are covered while the screenshot is taken (best effort). Black out anything else private before you send: blacked-out areas are removed from the uploaded image, together with the captured text under them.
- Send, or collect several notes into a review session and publish them together.
- Numbered pins show the feedback already left on the page and its status.
- In the TweakThis dashboard, your coding agent claims an item, changes the code and submits a summary; you or your client accept the fix or reopen it.

What it sends, and when
TweakThis captures a page only when you pick something to give feedback on or record a guided flow, and sends it only to your TweakThis account (tweakthis.io and its storage), when you press Send. When you open its menu or pins on a project page, it uses the page address to load the feedback already left there. Firefox asks you at install to allow this (website content, the page address, your activity while you record a guided flow, and your TweakThis sign-in). If you also allow technical data, TweakThis reports when a site-access prompt was declined or a capture could not start (no address or content). It does not track your browsing, show ads or sell data.

Permissions
- "Store unlimited amount of client-side data": feedback you have written but not sent yet keeps its screenshots on your computer until it is uploaded, so Firefox does not delete it when disk space runs low.
- Access to tweakthis.io: the TweakThis service it sends your feedback to.
- Access to other sites is asked for one site at a time, only after you click: "Select an element" on a page of one of your projects (declining still lets you capture through the toolbar button), or "Allow access to <site>" when the picker cannot start on the current tab.

What you need
A TweakThis account (sign in from the extension). Clients you invite report for free. Agents connect through the TweakThis MCP server; see https://tweakthis.io for setup.