Lighthouse agentic browsing scoring | Chrome for Developers

Skip to main content

English

Deutsch

Español – América Latina

Français

Indonesia

Italiano

Nederlands

Polski

Português – Brasil

Tiếng Việt

Türkçe

Русский

עברית

العربيّة

فارسی

हिंदी

বাংলা

ภาษาไทย

中文 – 简体

中文 – 繁體

日本語

한국어

Sign in

Docs

Lighthouse

Home

Docs

Lighthouse

Agentic browsing audits

Lighthouse agentic browsing scoring

Stay organized with collections

Save and categorize content based on your preferences.

Note: The Agentic Browsing category and WebMCP support are experimental<br>and based on proposed standards. Testing this category requires Chrome 150<br>or later, and WebMCP audits require registering for the<br>WebMCP origin trial.

The Agentic Browsing category evaluates how well your site is constructed for<br>machine interaction through a set of deterministic audits.

How the category is scored

Unlike other Lighthouse categories, the Agentic Browsing category does not have<br>a weighted average score from 0 to 100. Because the standards for the agentic<br>web are still emerging, the current focus is to gather data and provide<br>actionable signals rather than a definitive ranking.

Instead of a score, the report displays:

A fractional score : A ratio showing how many agentic readiness checks<br>your site passes.

Pass or Fail status : Specific audits may emit errors or warnings if<br>technical requirements (like WebMCP schema validity) are not met.

Informational counts : The category header may include a pass ratio to<br>help you observe overall progress at a glance.

Why results fluctuate

While the audits are deterministic, your results may fluctuate due to changes in<br>how your site registers its tools or responds to agentic requests. Common causes<br>include:

Dynamic tool registration : If your site registers WebMCP tools using<br>JavaScript (Imperative API), the timing of<br>these registrations can affect whether they are captured during<br>the Lighthouse snapshot.

Variability in A11y tree construction : Significant changes to DOM size<br>or complexity can impact the structure of the accessibility tree, which is a<br>core metric for agentic navigation.

Cumulative Layout Shift (CLS) : Layout shifts caused by ads, images<br>without dimensions, or injected content can move elements between the time<br>an agent identifies them and the time it attempts an interaction.

How audits are determined

Lighthouse uses a set of deterministic signals to evaluate your page. This<br>ensures that the audits are reproducible and suitable for integration into CI/CD<br>pipelines.

WebMCP Integration

Lighthouse calls the Chrome DevTools Protocol (CDP) WebMCP domain to monitor<br>tool registration events. It verifies both declarative tools (defined in HTML)<br>and imperative tools (defined in JS).

Agent-Centric Accessibility

Agents rely on the accessibility tree as their primary data model. Lighthouse<br>filters a specific subset of accessibility audits that are critical for machine<br>interaction, such as:

Names and labels : Ensuring every interactive element has a programmatic<br>name.

Tree integrity : Verifying that roles and parent-child relationships are<br>valid.

Visibility : Confirming that content is not hidden from the accessibility<br>tree while being interactive.

Stability and Discoverability

Cumulative Layout Shift (CLS) : Measures visual stability, which is<br>critical for agents relying on element positioning.

llms.txt : Checks for the presence of a machine-readable summary at the<br>domain root.

What can developers do to improve?

To improve your site's agentic readiness:

Adopt WebMCP : Use the WebMCP API to explicitly expose your site's logic<br>and forms to AI agents.

Ensure a sound a11y tree : Prioritize semantic HTML and proper ARIA<br>labeling, as these are the "machine-eye view" of your page.

Optimize for stability : Reduce layout shifts to ensure that agents can<br>reliably interact with your UI without elements moving unexpectedly.

Feedback

If you encounter bugs or have suggestions for changes to the agentic browsing<br>audit:

File an issue on GitHub

Except as otherwise noted, the content of this page is licensed under the Creative Commons Attribution 4.0 License, and code samples are licensed under the Apache 2.0 License. For details, see the Google Developers Site Policies. Java is a registered trademark of Oracle and/or its affiliates.

Last updated 2026-05-05 UTC.

[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2026-05-05 UTC."],[],[]]