Stunt Double Index
More of your visitors arrive through an AI agent: someone asks ChatGPT, Claude, Gemini or Perplexity to compare products, find an answer or check out on their behalf. The Stunt Double Index measures how that goes on your site, and ranks it against everyone else.
Each tracked domain gets a score out of 100, a band and a rank, overall and within its sector. Index data is public, so you can read any tracked site's report, including your competitors'.
How a site is scored
A score comes from two kinds of evidence:
- Probes. HTTP checks that look at what agents depend on, such as whether pages are server-rendered, structured data is present and agents are allowed in. Each failing check is listed with its weight.
- Agent sessions. Live sessions, one per AI provider and benchmark task, where an agent tries a real job on the site. Each session records what the agent tried, its rubric evidence, a summary and the frictions it hit.
A full run is the probes plus about 24 agent sessions. Stunt Double runs the sessions on the same browser toolset its actors use.
What it measures
| Category | Can an agent... |
|---|---|
| Brand awareness | Recognize the brand and what it offers |
| Discovery | Find the site and the right page for a task |
| Information retrieval | Read the facts it needs from the site |
| Market ranking | Place the site among its competitors |
| Accuracy | Report what the site says without getting it wrong |
| Checkout | Get through to buying, on a person's behalf |
| Delegated access | Act for a signed-in person |
| Support | Find help content and get an answer |
The report also breaks the score down by provider, so you can see when one agent struggles where the others don't.
Add or claim a site
Anyone signed in can add a site that isn't tracked yet at index.stuntdouble.io. A new site gets light probes by default, with an option to add live agent sessions.
Claim your domain to re-score it after you ship changes.