README

Sites spend effort blocking AI crawlers. Crawlers spend effort getting around the blocks. Both lose.

laravel/mcp already makes it easy to expose structured tools (search, get_article, …) over MCP. What's missing is the signpost: a way for an agent landing on your site to learn "there's an MCP server here, use that".

This package adds the signpost. It reads the servers you registered with Mcp::web() and publishes them through the discovery standards that are emerging. You can switch each one on or off in config.

#[Discoverable(name: 'com.example/blog', primary: true)]
class BlogServer extends Server { /* ... */ }

$ curl https://example.com/.well-known/mcp-server-card
{ "name": "com.example/blog", "remotes": [{ "type": "streamable-http", "url": "https://example.com/mcp/blog" }], ... }

Status: pre-release (0.x). The standards underneath are still moving, so expect config keys and output formats to follow them.

What it does

Feature	Standard	Default
Server Cards at `/.well-known/mcp-server-card[/{key}]`	MCP SEP-2127 (in review)	on
`llms.txt` section listing your MCP servers	llms.txt	on
`robots.txt` MCP pointers + Content Signals	Content Signals, IETF aipref	off
`Link: <…>; rel="mcp"` header on HTML responses	Proposal (not IANA-registered)	off
`Accept: text/markdown` → always send the MCP `Link` header	Mirrors Cloudflare's Markdown for Agents	off
A2A Agent Card at `/.well-known/agent-card.json`	A2A	off
Bot gate: redirect-instead-of-reject (`403`/`402` + `Link` + short body)	Proposal	off
Web Bot Auth signature verification (signed agents get through, unsigned get gated)	IETF webbotauth	off
`server.json` generation for the MCP Registry	MCP Registry	command

Each standard lives in its own emitter class, so a spec change touches only one file.

Requirements

PHP 8.3+
Laravel 12 or 13
laravel/mcp ^1.0
ext-sodium if you use Web Bot Auth. It ships with most PHP builds.

Installation

composer require pietervanleuven/laravel-mcp-discovery

Optionally publish the config file:

php artisan vendor:publish --tag="mcp-discovery-config"

Make sure APP_URL is set to your public, canonical URL. All discovery URLs are built from APP_URL, never from the request's Host header, so publicly cached cards can't be poisoned.

Quick start

1. Register your server as usual

Nothing about how laravel/mcp works changes:

// routes/ai.php
use App\Mcp\Servers\BlogServer;
use Laravel\Mcp\Facades\Mcp;

Mcp::web('/mcp/blog', BlogServer::class)
    ->middleware('throttle:mcp');

2. Mark it `#[Discoverable]`

namespace App\Mcp\Servers;

use App\Mcp\Tools\GetArticle;
use App\Mcp\Tools\SearchArticles;
use Laravel\Mcp\Server;
use Laravel\Mcp\Server\Attributes\Instructions;
use Laravel\Mcp\Server\Attributes\Name;
use Laravel\Mcp\Server\Attributes\Version;
use PieterVanLeuven\McpDiscovery\Attributes\Discoverable;

#[Name('Blog')]
#[Version('1.0.0')]
#[Instructions('Search and read articles from example.com.')]
#[Discoverable(name: 'com.example/blog', primary: true)]
class BlogServer extends Server
{
    protected array $tools = [
        SearchArticles::class,
        GetArticle::class,
    ];
}

3. Check what's published

php artisan mcp-discovery:list
php artisan mcp-discovery:validate

+------+------------------+---------+------------------------------+------+---------+--------+-------+
| Key  | Name             | Version | URL                          | Auth | Primary | Public | Tools |
+------+------------------+---------+------------------------------+------+---------+--------+-------+
| blog | com.example/blog | 1.0.0   | https://example.com/mcp/blog | none | yes     | yes    | 2     |
+------+------------------+---------+------------------------------+------+---------+--------+-------+

That's it. You now have:

GET /.well-known/mcp-server-card
Content-Type: application/json
Access-Control-Allow-Origin: *
Cache-Control: max-age=3600, public

{
    "$schema": "https://static.modelcontextprotocol.io/schemas/v1/server-card.schema.json",
    "name": "com.example/blog",
    "version": "1.0.0",
    "title": "Blog",
    "description": "Search and read articles from example.com.",
    "websiteUrl": "https://example.com",
    "remotes": [
        {
            "type": "streamable-http",
            "url": "https://example.com/mcp/blog",
            "supportedProtocolVersions": ["2026-07-28"]
        }
    ]
}

and GET /llms.txt:

# Example

> Example exposes structured tools for AI agents over MCP.

<!-- mcp-discovery:start -->
## MCP servers

This site offers its content over the Model Context Protocol (MCP). Agents should connect to these servers instead of scraping HTML.

- [Blog](https://example.com/mcp/blog): Search and read articles from example.com. Streamable HTTP endpoint. Server card: https://example.com/.well-known/mcp-server-card
<!-- mcp-discovery:end -->

Where metadata comes from

Each value is resolved from these sources in order. Later sources win.

laravel/mcp attributes and properties on the server: #[Name] → title, #[Version], #[Instructions], #[Title], #[Description], #[Icon]
#[Discoverable(...)]
The server's entry in config('mcp-discovery.servers')

Field	Default when nothing is set
`key` (URL segment)	Class name without `Server`, kebab-cased: `BlogServer` → `blog`
`name` (registry name)	Reverse-DNS of `APP_URL` + key: `https://example.com` → `com.example/blog`
`title`	`#[Title]`, else `#[Name]`
`description`	`#[Description]`, else the first paragraph of the instructions (max 100 chars)
`url`	Absolute URL of the `Mcp::web()` route (domain routes supported)
`protocol_versions`	What the `laravel/mcp` server advertises
`auth`	Inferred from route middleware (see below)
`primary`	The first server, if none is marked

Auth inference. auth:api (or any non-Sanctum guard) combined with Mcp::oauthRoutes() means oauth: the card stays minimal and clients discover OAuth through the WWW-Authenticate header, as the MCP spec describes. auth:sanctum (or auth without OAuth routes) means bearer: the card lists a required secret Authorization header in remotes[].headers.

`#[Discoverable]` reference

#[Discoverable(
    key: 'blog',                          // /.well-known/mcp-server-card/blog
    name: 'com.example/blog',             // reverse-DNS, used by the MCP Registry
    title: 'Example Blog',
    description: 'Search and read articles.',
    primary: true,                        // served at /.well-known/mcp-server-card
    public: true,                         // false = only for logged-in users / verified agents
    websiteUrl: 'https://example.com/blog',
    repository: ['url' => 'https://github.com/acme/site', 'source' => 'github'],
)]

Configuring servers explicitly

Prefer config over attributes, or need to expose a server that lives elsewhere? Replace 'auto' with a map:

// config/mcp-discovery.php
'servers' => [
    'blog' => [
        'class' => App\Mcp\Servers\BlogServer::class,
        'name' => 'com.example/blog',
        'primary' => true,
    ],

    // Not registered with Mcp::web() in this app: give a URL.
    'search' => [
        'class' => App\Mcp\Servers\SearchServer::class,
        'url' => 'https://search.example.com/mcp',
        'auth' => 'oauth', // 'none' | 'oauth' | 'bearer'
    ],

    // Shorthand: key derived from the class.
    App\Mcp\Servers\ShopServer::class,
],

In explicit mode #[Discoverable] is optional, and config values override it. Any descriptor field can be set: name, title, description, version, url, website_url, repository, icons, protocol_versions, auth, primary, public.

Emitters

Every emitter is configured under mcp-discovery.emitters.{key} and has an enabled flag and a class.

Server Cards

'server_card' => [
    'enabled' => true,
    'path' => '.well-known/mcp-server-card',  // SEP-2127 revisions disagree; follow whichever is merged
    'index_path' => null,                      // e.g. '.well-known/mcp/server-cards.json'
    'cache' => 3600,
    'include_capabilities' => false,
],

GET /{path} serves the primary server. GET /{path}/{key} serves any server.
index_path adds one document listing every card: {"servers": [ {...card, "_links": {"self": "…"}} ]}.
include_capabilities adds capabilities, tools, resources and prompts (name, title, description) so agents can see what a server does before connecting. It is off by default because not every site wants its tool surface public. Tools that use shouldRegister() are respected.
Non-public servers return 404 unless the request comes from a logged-in user or a verified Web Bot Auth agent, and are then served with Cache-Control: private, no-store.

`llms.txt`

'llms_txt' => [
    'enabled' => true,
    'mode' => 'route',   // 'route' | 'file'
    'base' => null,      // e.g. resource_path('llms.txt')
],

There are two ways to ship it, because a static public/llms.txt is served by your web server before Laravel ever runs:

route mode (default). The package serves /llms.txt dynamically. Put your hand-written content in a file outside public/ and point base at it; the MCP section is appended.

'base' => resource_path('llms.txt'),

file mode. Keep your static public/llms.txt and let the package maintain a marked section in it:

php artisan mcp-discovery:write            # writes/updates the section
php artisan mcp-discovery:write --dry-run  # prints the result

The section sits between  and . Everything outside the markers is left alone, and re-running the command is idempotent. Add it to your deploy script. mcp-discovery:validate warns when the file is out of date, or when a static file shadows the route.

`robots.txt`

'robots_txt' => [
    'enabled' => true,
    'mode' => 'file',  // Laravel ships public/robots.txt, so 'file' is the usual choice
    'content_signals' => ['search' => 'yes', 'ai-input' => 'yes', 'ai-train' => 'no'],
],

php artisan mcp-discovery:write

User-agent: *
Disallow:

# mcp-discovery:start
# MCP server (com.example/blog): https://example.com/mcp/blog
# MCP server card: https://example.com/.well-known/mcp-server-card
User-agent: *
Content-Signal: search=yes, ai-input=yes, ai-train=no
# mcp-discovery:end

robots.txt has no directive for MCP, so the pointers are comments. The emitter never adds Allow/Disallow rules: crawlers merge groups for the same user agent, and an extra Allow: / could override your own rules.

`Link` header

'link_header' => [
    'enabled' => true,
    'rel' => 'mcp',
    'only' => 'bots',  // 'bots' | 'all'
],

HTML responses in the web middleware group get:

Link: <https://example.com/mcp/blog>; rel="mcp"; title="Blog"
Link: <https://example.com/.well-known/mcp-server-card>; rel="service-desc"; type="application/json"

rel="service-desc" is RFC 8631. rel="mcp" isn't registered yet. With only => 'bots', the header is added only for requests the bot detector flags. If you put a shared cache in front of the site, either use 'all' or make sure the cache varies on User-Agent.

Markdown hint

'markdown_hint' => ['enabled' => true],

Requests sending Accept: text/markdown are almost always agents. They get the MCP Link header on every response, whatever its content type, plus Vary: Accept.

A2A Agent Card

'a2a_agent_card' => [
    'enabled' => true,
    'url' => 'https://example.com/a2a',  // your A2A endpoint
],

Serves /.well-known/agent-card.json built from the primary server, with each tool as a skill. Only enable this if you actually run an A2A endpoint. The MCP endpoint does not speak A2A, and mcp-discovery:validate warns when url is missing.

Bot gate: redirect instead of reject

Instead of blocking AI crawlers (and watching them rotate user agents), tell them where the good stuff is:

'bot_gate' => [
    'enabled' => true,
    'response' => 403,  // 403 | 402 | 'pass'
    'except' => ['/', 'robots.txt', 'llms.txt', '.well-known/*'],
    'allow' => ['Googlebot', 'Bingbot', 'DuckDuckBot', 'Applebot', 'YandexBot'],
    'user_agents' => [],  // extra UA fragments to treat as AI bots
],

$ curl -i -A "ClaudeBot/1.0" https://example.com/articles/hello
HTTP/1.1 403 Forbidden
Content-Type: text/plain; charset=UTF-8
Cache-Control: no-store, private
Link: <https://example.com/mcp/blog>; rel="mcp"; title="Blog"
Link: <https://example.com/.well-known/mcp-server-card>; rel="service-desc"; type="application/json"

Automated access to this page is not available.
This site offers its content over MCP (Model Context Protocol):

- Blog: https://example.com/mcp/blog
  server card: https://example.com/.well-known/mcp-server-card

Clients that send Accept: application/json get the same information as JSON. 'response' => 'pass' serves the page as normal and only adds the Link header. 402 is there for sites experimenting with paid access.

Search crawlers in allow always get HTML. Paths in except are never gated. If there are no public servers, the gate does nothing.

Custom bot detection

The built-in UserAgentDetector is deliberately simple. Swap it for anything that implements Detector, for example Cloudflare's verified-bot signal:

namespace App\Bots;

use Illuminate\Http\Request;
use PieterVanLeuven\McpDiscovery\Bots\Detector;
use PieterVanLeuven\McpDiscovery\Bots\UserAgentDetector;

class CloudflareDetector implements Detector
{
    public function __construct(protected UserAgentDetector $fallback) {}

    public function isBot(Request $request): bool
    {
        // Requires a Transform Rule that copies cf.verified_bot_category into this header.
        if ($request->header('X-Verified-Bot-Category') === 'AI Crawler') {
            return true;
        }

        return $this->fallback->isBot($request);
    }
}

'bot_gate' => ['detector' => App\Bots\CloudflareDetector::class, /* ... */],

Web Bot Auth

Agents that sign their requests with HTTP Message Signatures (Web Bot Auth) can prove who they are. Enable verification and signed agents get through, while everyone else pretending to be them gets gated:

'bot_gate' => [
    'enabled' => true,
    'web_bot_auth' => [
        'enabled' => true,
        'unsigned' => 'block',   // 'block' = gate unsigned bots; 'pass' = let them through with the Link header
        'directory_cache' => 3600,
        'max_age' => 300,
    ],
],

Request	Result
Valid signature	Page served, plus `Link` header. Non-public server cards become visible.
Signature present but invalid, expired, for another host or with an unknown key	Gated
Unsigned, detected as a bot	Gated (`block`) or served with the `Link` header (`pass`)
Unsigned, not a bot	Served normally

The verifier fetches the agent's key directory from Signature-Agent + /.well-known/http-message-signatures-directory, matches keyid to a JWK thumbprint (RFC 7638) and checks the Ed25519 signature over the covered components (@authority, signature-agent, @method, @path, headers, …). Key directories are cached, and only https agents are accepted.

Registering the middleware yourself

By default, BotGate and AddDiscoveryHeaders are appended to the web group, but only when a feature that needs them is enabled. To control placement yourself:

// config/mcp-discovery.php
'register_middleware' => false,

// bootstrap/app.php
use PieterVanLeuven\McpDiscovery\Http\Middleware\AddDiscoveryHeaders;
use PieterVanLeuven\McpDiscovery\Http\Middleware\BotGate;

->withMiddleware(function (Middleware $middleware) {
    $middleware->web(append: [BotGate::class, AddDiscoveryHeaders::class]);
})

Publishing to the MCP Registry

php artisan mcp-discovery:publish-registry        # primary server
php artisan mcp-discovery:publish-registry shop --output=registry/shop.json

This writes a server.json in the registry format and prints the mcp-publisher commands to run. The registry verifies you own the namespace, so com.example/* needs DNS or HTTP verification of example.com. That's why names default to the reverse-DNS form of APP_URL.

Artisan commands

Command	What it does
`mcp-discovery:list [--json]`	Servers and emitters, as the package sees them
`mcp-discovery:validate`	Checks names, versions, HTTPS, description length, duplicate primaries, stale or shadowed `llms.txt`/`robots.txt`. Exits non-zero on errors, so it can run in CI.
`mcp-discovery:write [--dry-run]`	Updates `public/llms.txt` and `public/robots.txt` for emitters in `file` mode
`mcp-discovery:publish-registry [server] [--output=]`	Generates `server.json` for the MCP Registry

Using the descriptors in your own code

use PieterVanLeuven\McpDiscovery\Facades\McpDiscovery;

$primary = McpDiscovery::servers()->primary();

$primary->name;          // 'com.example/blog'
$primary->url;           // 'https://example.com/mcp/blog'
$primary->tools();       // [['name' => 'search-articles', 'title' => ..., 'description' => ...], ...]

McpDiscovery::cardUrl($primary);   // 'https://example.com/.well-known/mcp-server-card'
McpDiscovery::linkValues();        // ready-made Link header values

For example, advertise the server in your HTML <head> too:

@use('PieterVanLeuven\McpDiscovery\Facades\McpDiscovery')

@foreach (McpDiscovery::servers()->visible() as $server)
    <link rel="mcp" href="{{ $server->url }}" title="{{ $server->title }}">
@endforeach

Writing your own emitter

A new discovery standard means adding one class. Extend Emitter, register routes if it serves something, and implement ProvidesLinks or WritesPublicFile if it adds headers or file sections:

namespace App\Discovery;

use Illuminate\Routing\Router;
use PieterVanLeuven\McpDiscovery\Emitters\Emitter;

class McpManifestEmitter extends Emitter
{
    public function routes(Router $router): void
    {
        $router->get('.well-known/mcp', fn () => response()->json([
            'servers' => $this->discovery->servers()->visible()
                ->map(fn ($server) => ['name' => $server->name, 'url' => $server->url])
                ->values(),
        ]));
    }
}

'emitters' => [
    // ...
    'mcp_manifest' => ['enabled' => true, 'class' => App\Discovery\McpManifestEmitter::class],
],

The same works for replacing a built-in emitter: point its class at your subclass.

Caveats

Route caching. With php artisan route:cache, laravel/mcp doesn't load routes/ai.php, so the package finds servers by scanning the cached routes instead. Discovery routes are registered at boot and cached along with your own. Re-run route:cache after changing emitter config.
Octane. Services are scoped, so descriptors are rebuilt per request.
One route per class. If a server class is registered at several URLs, the first one is published. Use explicit config with a url to pick another.
App routes win. If your app defines its own /llms.txt or /robots.txt route, it overrides the package's.

Roadmap

Server Cards, list/validate commands
llms.txt, robots.txt, Link header
Bot gate with a pluggable detector
Web Bot Auth verification, A2A card, registry server.json
WebMCP bridge script (navigator.modelContext)
SEP-1960 /.well-known/mcp manifest emitter (if it gets merged)
x402 / 402 payment hook (probably a separate package)
mcp-discovery:cache for fully static cards

Testing

composer test       # Pest
composer analyse    # PHPStan (level 6)
composer format     # Pint

Changelog

See CHANGELOG.

Contributing

See CONTRIBUTORS. If you're an AI coding agent, read AGENTS.md first.

Security Vulnerabilities

Please review our security policy on how to report security vulnerabilities.

Credits

References

Laravel MCP: https://laravel.com/docs/mcp
SEP-2127 MCP Server Cards: modelcontextprotocol/modelcontextprotocol#2127
MCP Registry: https://registry.modelcontextprotocol.io/
llms.txt: https://llmstxt.org/
Content Signals: https://contentsignals.org/
IETF AI Preferences: https://datatracker.ietf.org/wg/aipref/about/
Web Bot Auth: https://datatracker.ietf.org/doc/draft-meunier-web-bot-auth-architecture/
RFC 9421 HTTP Message Signatures: https://www.rfc-editor.org/rfc/rfc9421
A2A: https://a2a-protocol.org/
Cloudflare Markdown for Agents: https://developers.cloudflare.com/fundamentals/reference/markdown-for-agents
WebMCP: https://webmachinelearning.github.io/webmcp/

License

The MIT License (MIT). Please see License File for more information.

pietervanleuven / laravel-mcp-discovery

Package info

Security

Statistics

README

What it does

Requirements

Installation

Quick start

1. Register your server as usual

2. Mark it `#[Discoverable]`

3. Check what's published

Where metadata comes from

`#[Discoverable]` reference

Configuring servers explicitly

Emitters

Server Cards

`llms.txt`

`robots.txt`

`Link` header

Markdown hint

A2A Agent Card

Bot gate: redirect instead of reject

Custom bot detection

Web Bot Auth

Registering the middleware yourself

Publishing to the MCP Registry

Artisan commands

Using the descriptors in your own code

Writing your own emitter

Caveats

Roadmap

Testing

Changelog

Contributing

Security Vulnerabilities

Credits

References

License

pietervanleuven / laravel-mcp-discovery

Package info

Security

Statistics

README

What it does

Requirements

Installation

Quick start

1. Register your server as usual

2. Mark it #[Discoverable]

3. Check what's published

Where metadata comes from

#[Discoverable] reference

Configuring servers explicitly

Emitters

Server Cards

llms.txt

robots.txt

Link header

Markdown hint

A2A Agent Card

Bot gate: redirect instead of reject

Custom bot detection

Web Bot Auth

Registering the middleware yourself

Publishing to the MCP Registry

Artisan commands

Using the descriptors in your own code

Writing your own emitter

Caveats

Roadmap

Testing

Changelog

Contributing

Security Vulnerabilities

Credits

References

License

2. Mark it `#[Discoverable]`

`#[Discoverable]` reference

`llms.txt`

`robots.txt`

`Link` header