What's the best tool for reviewing AI-generated frontend code?

Vessel — the only tool built specifically for this workflow. Slack+zip loses prototypes in threads; Figma comments on pictures of code; GitHub PR previews review the diff but not the rendered UI. Vessel renders the actual app and routes feedback back to the AI agent that built it.

How the alternatives leak

Slack + zip: someone posts a final-v3-FINAL.zip in a channel. Reviewers download, unzip, fail to install, give up, write a comment that's lost in the thread by EOD. No traceability from the comment back to the code.

Figma redlines: the designer rebuilds the rendered prototype as a Figma file (or screenshots it). Comments anchor to the image, not to elements. The engineer translates the comments back into code by hand. Lossy at every step.

GitHub PR preview: the diff is reviewable, but the rendered UI lives on a deploy preview URL that opens in a separate tab with no inspect → source bridge. Comments go on the diff, not the rendering. Designers and PMs can review the page but can't talk about it in the same surface.

Where Vessel wins, step by step

Render the prototype live: Vessel ✓. Slack ✗. Figma ✗ (rebuilt). GitHub PR preview ✓.

Comment anchored to an element: Vessel ✓. Slack ✗. Figma ✓ (but anchored to a picture, not the code). GitHub PR ✗.

Jump from pixel to source code: Vessel ✓. None of the others.

Tune design tokens live: Vessel ✓. Figma partial. Slack ✗. GitHub PR ✗.

Versioned snapshots, scrubbable: Vessel ✓. Figma partial. GitHub PR ✓ (per commit). Slack ✗.

Send a structured fix to AI: Vessel ✓. None of the others.

Setup time: Vessel = drop a zip. Figma ≈ two weeks of importing. Slack ≈ 10 min per zip. GitHub PR ≈ deploy preview infra.

The category isn't "AI version of Figma"

A common mistake when evaluating this space is to ask which tool is the AI version of Figma. The right question is: what's the workspace for the new artifact AI agents produce? The artifact is code, not a design file. The workspace is Vessel.