# What is an MCP endpoint and does your site need one?

*2026-06-07 · Agent Surface & Observability*

> The Model Context Protocol lets AI agents use your site's functionality directly, not just read about it. Here's what that means for marketing managers.

## Readable versus usable

Most of this site's framework is about making your content *readable* to AI: structured
data, llms.txt, clean semantic HTML. The Agent Surface pillar is about something further
along — making your site *usable* by AI. The difference is the difference between an
assistant describing your tool and an assistant running it.

The Model Context Protocol (MCP) is the emerging standard for that second thing.

## What MCP actually is

MCP is an open protocol that defines how an AI agent discovers and calls external tools
and data sources in a consistent way. An MCP server exposes a set of capabilities — for
example *"check a URL's AI readiness"* or *"look up product availability"* — that any
MCP-aware assistant can invoke, with typed inputs and structured outputs.

Concretely, instead of a human visiting your site and clicking a button, an agent can
call your endpoint, get a structured result, and fold it into whatever it's doing for its
user.

## Does your site need one?

Be honest about your shape:

- **Content / brochure sites** — probably not yet. Your priority is being *readable*: schema, llms.txt, answer units. An MCP endpoint with nothing to invoke is theatre.
- **Tools, calculators, audit products** — increasingly yes. If the value of your site is a *function*, an agent that can call that function for its user is a powerful new distribution channel.
- **Data providers** — yes, trending toward essential. If people query your data, agents will want to as well.

## The defensibility flip side

Exposing a callable surface means thinking about abuse: rate limiting, authentication
where appropriate, scraper detection, and GDPR-compliant handling of anything personal
that flows through. Agent accessibility and agentic defensibility are two sides of the
same coin — see the framework's [Agent Surface pillar](/framework#agent).

## Where this site is heading

In Phase 3, the AI Readiness audit on this site becomes MCP-callable: an agent will be
able to run a readiness check on a user's URL directly. That's the canonical example —
a tool whose value multiplies the moment agents can invoke it.

## What to do this week

1. Decide whether your site's value is *content* or a *function*.
2. If it's content, finish the readability pillars first — don't skip ahead.
3. If it's a function, sketch the one or two capabilities an agent would call.
4. Plan rate limiting and data handling before you expose anything.