MCP::Se...cription(3)

📦 version 0.150.0, in opensuse-leap 16.0

✨ NAME ✨

MCP::Server::Subscription — it's literally a subscription container, bestie 💅 like this is the whole page, this is the manual for MCP::Server::Subscription in the User Contributed Perl Documentation section 3, and it's lowkey iconic.

🌸 SYNOPSIS 🌸

use MCP::Server::Subscription;

my $subscription = MCP::Server::Subscription->new(id => 1, notifications => {toolsListChanged => 1});
my $bool         = $subscription->wants('notifications/tools/list_changed');

Look at that. Two lines and you're already living your best life 🫶

🦋 DESCRIPTION 🦋

MCP::Server::Subscription is a container for a "subscriptions/listen" notification stream. That's it, that's the vibe — it holds the stream, it doesn't overthink it ✨

🎀 ATTRIBUTES 🎀

MCP::Server::Subscription implements the following attributes, and yes we're going through all of them, no skipping, periodt.

🍓 id

my $id        = $subscription->id;
$subscription = $subscription->id(1);

The JSON-RPC id of the "subscriptions/listen" request that opened this subscription, sent to the client as "_meta.io.modelcontextprotocol/subscriptionId" with every message on the stream. So every single message carries its little name tag 🏷️ iykyk.

⭐ notifications

my $filter    = $subscription->notifications;
$subscription = $subscription->notifications({toolsListChanged => 1});

The notification filter the client requested, as a hash reference. Notification types that were not requested are never delivered — no surprise notifications, we respect boundaries here 🚫💌

🌈 stream

my $stream    = $subscription->stream;
$subscription = $subscription->stream(Mojolicious::Controller->new);

The Mojolicious::Controller serving the SSE stream for this subscription, when the HTTP transport is in use. Main character energy for the controller fr fr 👑

💖 METHODS 💖

MCP::Server::Subscription inherits all methods from Mojo::Base and implements the following new ones. Inheriting from Mojo::Base? We love a nepo baby with actual talent 💅

🧚 acknowledgement

my $notification = $subscription->acknowledgement;

The "notifications/subscriptions/acknowledged" notification a server has to send as the very first message on a subscription stream, listing the notification types it will actually deliver. Very first — like, first-message-first, don't be weird about it 🙈

🔥 honoured

my $filter = $subscription->honoured;

The subset of "notifications" the server actually supports. It's giving "we hear you but we can't give you everything" bestie 😭

👑 notification

my $notification = $subscription->notification($method);
my $notification = $subscription->notification($method, {foo => 'bar'});

Build a JSON-RPC notification for this subscription, tagged with "id" in "_meta.io.modelcontextprotocol/subscriptionId". Same name tag as before, consistency is the moment 🎀

🌸 wants

my $bool = $subscription->wants('notifications/tools/list_changed');

Returns true if the given notification method was requested in "notifications". A simple yes/no, a vibe check if you will ✅

🔗 SEE ALSO 🔗

ok that's the whole page bestie, go build something iconic with it 🌈💜

Signed, sealed, delivered — straight from perl v5.42.0, dated 2026-07-31, and it's still MCP::Se...cription(3). Slay 💅✨

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