Tools for a web that agents read.

Sitebulb Labs is where Sitebulb tries out ideas ahead of its main products. The first is a Chrome extension that checks how well a site is set up for AI agents.

What Labs is

Sitebulb is a website auditing tool. It crawls a site and tells you what a search engine would make of it. In the last couple of years a second kind of visitor has arrived: AI agents that fetch pages on someone’s behalf, look for files likellms.txt, and probe for protocols that let them do more than read.

How those agents read the web is still being worked out, and the standards they rely on are being written in public, in real time. Labs exists to follow that work closely, build small tools that make it visible, and find out which of it matters before it is settled enough to belong in Sitebulb itself.

From
Sitebulb Limited, the team behind Sitebulb.
First project
The Sitebulb Labs Extension for Chrome.
Where it runs
In your browser. Nothing is sent to our servers.

What we’re aiming for

Six things every Labs project should be able to say about itself.

  1. Work out how AI agents read the web

    Agents fetch pages, follow well-known files and look for protocols that did not exist two years ago. We want to understand what they actually need from a site, and turn that into checks people can run.

  2. Track the standards while they are still moving

    llms.txt, MCP server cards, Web Bot Auth, x402, UCP, ACP and the rest are being written now. Labs is where we follow them as they settle, rather than waiting until they are finished to take an interest.

  3. Ship small tools quickly

    Labs projects are deliberately narrow. Each one answers a specific question, ships early, and is allowed to change shape as we learn what is useful.

  4. Be honest about what is known

    Where a standard has not settled, a tool should say so instead of marking a site down. A missing file that almost nobody publishes yet is a fact worth reporting, not a failure.

  5. Keep audit results in your browser

    Audit results stay in your browser. If you enable emerging checks, the extension sends the audited site’s hostname to Cloudflare for a DNS lookup. Nothing is sent to Sitebulb servers.

  6. Feed what we learn back into Sitebulb

    The point of experimenting is to find out what belongs in the main product. What holds up here informs what Sitebulb does next.