# WebMCP Tool

> webmcp-tool.com measures whether AI agents can read, understand and operate a
> website. It runs 23 documented checks across five pillars and returns one
> Agent Readiness Score out of 100, split into Fitness (does the site work for
> agents today) and Adoption (which agent protocols are in place). Free, no
> account, every finding carries the evidence it was based on.

Last reviewed: 2026-08-27.

## Start here
- [Run a check](https://webmcp-tool.com/#check): enter a public URL, get a score in about 20 seconds
- [Methodology](https://webmcp-tool.com/agent-readiness-score): every check, its weight and when it is excluded
- [What WebMCP is](https://webmcp-tool.com/what-is-webmcp): the standard, its state, and what it does not replace

## The five pillars
- Agent Access (20 points, fitness axis): Can an agent reach the page at all?
- Machine Readability (20 points, fitness axis): Can it understand what is on the page?
- Actionability (25 points, fitness axis): Can it finish the job?
- WebMCP Implementation (25 points, adoption axis): Are there tools an agent can call?
- Agent Interop & Commerce (10 points, adoption axis): Can other systems discover and transact with you?

## WebMCP reference
- [What WebMCP is, and what it is not](https://webmcp-tool.com/what-is-webmcp): A browser API that lets a page hand an AI agent a list of named, typed functions instead of a DOM to guess at. Here is the shape of it, the state of it, and the honest case for building on it now.
- [Registering WebMCP tools with JavaScript](https://webmcp-tool.com/webmcp/imperative-api): The imperative API is the stable path into the standard. What a good tool looks like, how the abort signal keeps a single-page app honest, and the mistakes that make an agent call the wrong function.
- [The declarative API: tools from forms you already have](https://webmcp-tool.com/webmcp/declarative-api): The cheapest possible entry into WebMCP is annotating a form and letting the browser derive the schema. It is also the part of the specification that is least finished — here is the state of it, without inventing attribute names.
- [Turning WebMCP on in Chrome](https://webmcp-tool.com/webmcp/chrome-setup): Flags, the origin trial, and the difference between the two. Plus how to confirm your tools registered, rather than assuming they did because the code ran.
- [WebMCP versus MCP, raw APIs and browser automation](https://webmcp-tool.com/webmcp/vs-mcp): Four ways an agent can reach your product, what each costs you, and the one question that decides between them: who is holding the credential.
- [The WebMCP security model, and the parts that are still open](https://webmcp-tool.com/webmcp/security): Session-based access is a genuine improvement over handing an agent an API key. It is not a complete threat model, and the specification says so. What to rely on, what to gate, and what to tell a compliance officer.
- [navigator.modelContext is deprecated. Move to document.modelContext](https://webmcp-tool.com/webmcp/migration): The specification relocated the API in July 2026 and Chrome 150 deprecated the old position while the origin trial still serves it. A short migration with a long tail of quiet breakage if you skip it.
- [Shipping WebMCP before the browsers catch up](https://webmcp-tool.com/webmcp/polyfill): A polyfill provides document.modelContext where the browser does not, a React hook ties registration to component lifecycle, and a relay bridges page tools to desktop clients. What each is for, and where the seams are.
## Guides
- [robots.txt for AI agents](https://webmcp-tool.com/guides/robots-txt-for-ai-agents): Which tokens matter, why the catch-all group is not a decision, and the longest-match rule that decides whether your own discovery endpoint is reachable.
- [Content that survives without JavaScript](https://webmcp-tool.com/guides/content-without-javascript): The most common and most expensive failure on the agentic web. Why an empty shell defeats the crawlers behind AI answers, how to tell whether you have one, and what to do when a rewrite is not on the table.
- [Forms an agent can actually fill](https://webmcp-tool.com/guides/forms-agents-can-use): The cheapest large improvement most sites can make. Labels, names, types and autocomplete tokens turn a guess into a certainty — and they are the same work the declarative WebMCP API will ask for.
- [Structured data: the one place you state facts](https://webmcp-tool.com/guides/structured-data-for-agents): Prose implies. JSON-LD asserts. Which types earn their keep for agent readiness, why validity matters more than volume, and the failure mode where markup and page disagree.
- [llms.txt: what it is, and what it is not](https://webmcp-tool.com/guides/llms-txt): A convention, not a standard, and ignored by Google Search. It is still worth publishing — because it is the one place you get to write the summary rather than hope one is inferred.
- [Discovery documents, and the robots.txt trap](https://webmcp-tool.com/guides/agent-discovery-documents): WebMCP tools only exist while a page is open. A discovery document is how an agent learns you exist before it arrives — and the most common failure is a site hiding its own manifest.
## Industries
- [Compatibility-driven commerce](https://webmcp-tool.com/industries/ecommerce): The shops agents help most are not the ones selling t-shirts. They are the ones where the customer has to hold six specifications in their head at once — and where a wrong purchase becomes a return.
- [SaaS consoles: let them bring their own agent](https://webmcp-tool.com/industries/saas): Your users already have an assistant that holds their context. Exposing tools costs you nothing per call and beats building an in-app agent they did not ask for.
- [Banking and insurance: read-only is the feature](https://webmcp-tool.com/industries/banking-insurance): No regulated business is letting an agent sign a contract in 2026. That is fine — the read half carries most of the customer value and almost none of the risk, and the session model is genuinely easier to defend than an API key.
- [Internal tools: the easiest first project](https://webmcp-tool.com/industries/internal-tools): No compliance surface, no public traffic, users who already work with agents, and a result you can measure in the first week. This is where to learn the standard before you point it at customers.

## Optional
- [About the check](https://webmcp-tool.com/about): what it does not do, and how to disagree with a finding
- [Implementation](https://webmcp-tool.com/services): the work we do when you would rather it was done