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# Catalyst::Plugin::MCP
Generic, app-agnostic Model Context Protocol (revision 2025-06-18) server plugin
for Catalyst, layered on `Catalyst::Plugin::JSONRPC::Server`. It owns the MCP
lifecycle, capability advertisement, and verb routing, and knows nothing about
your domain — you supply providers.
## Synopsis
```perl
package MyApp;
use Catalyst qw/
+Catalyst::Plugin::JSONRPC::Server
+Catalyst::Plugin::MCP
/;
__PACKAGE__->setup;
# in a controller action:
sub mcp :Path('/mcp') :Args(0) {
my ( $self, $c ) = @_;
$c->mcp_register_provider( $c->model('MCP::Tools') ); # ToolProvider
$c->mcp_register_provider( $c->model('MCP::Resources') ); # ResourceProvider
$c->mcp_dispatch; # reads the body, runs the MCP lifecycle, writes the reply
}
```
## Providers
Implement one of the shipped Moo::Roles per provider object:
- `Catalyst::Plugin::MCP::Role::ResourceProvider` — `list($cursor)`,
`templates`, `read($uri)`.
- `Catalyst::Plugin::MCP::Role::PromptProvider` — `list($cursor)`,
`get($name, $args)`.
- `Catalyst::Plugin::MCP::Role::ToolProvider` — `list($cursor)`,
`call($name, $args)`.
Capabilities advertised in `initialize` are derived from which roles your
registered providers consume. Pagination is pass-through: the cursor flows to
`list($cursor)` and your `nextCursor` flows back out. Tool execution failures
return a normal result with `isError => 1`; unknown tools/prompts/resources and
bad params become JSON-RPC errors (`-32602`, `-32002`).
## Configuration
```perl
__PACKAGE__->config(
'Catalyst::Plugin::MCP' => {
protocol_versions => ['2025-06-18'], # newest-first
server_info => { name => 'myapp', version => '1.0' },
},
);
```
