Module server 

The server API: what a handler is given, and what it is allowed to ask for.

What lives here

context::RequestContext is the argument every tool, resource and prompt handler receives. It carries the request’s identity — id, cancellation token, progress token — and holds the context::PeerSession that negotiated it. context::CallbackExchange and the frame sink are declared here, in the module that consumes them, rather than collected into a shared ports module.

builder::Server is the value a user of this crate builds: a registry, a set of tool handlers, and a name. It binds nothing and runs nothing — the transports in T13 and T14 give it somewhere to run, and until then a test can drive it in-process.

error::GatedError is what a handler gets when it asks for something this session did not negotiate.

dispatch::Dispatcher is the method table: it turns a peer’s method name into a call on builder::Server, and is what a transport holds once the frames are decoded. It is separate from the builder because describing a server and routing a request against it are different jobs, and only the second one is I/O-shaped.

The boundary this module sits on

The session engine below in super::session is protocol-neutral: it holds an opaque profile handle and never names a version, so an A2A or ACP session can use it unchanged. This module is the MCP-facing facade over that core, and it is allowed to speak MCP because a user of a library does not want to be handed an opaque handle when asking “can I elicit here?” is the question they actually have. The core stays neutral; the facade does not have to.

Re-exports

pub use builder::BoxFuture;

pub use builder::DispatchError;

pub use builder::Server;

pub use builder::ServerBuilder;

pub use builder::ToolHandler;

pub use context::CallbackExchange;

pub use context::DynExchange;

pub use context::ExchangeError;

pub use context::PeerSession;

pub use context::RequestContext;

pub use context::StateMap;

pub use dispatch::Dispatcher;

pub use error::GatedError;

pub use live::ListKind;

pub use live::ListSubscription;

pub use live::ServerHandle;

pub use log_gate::LogGate;

pub use result::OutcomeError;

Modules

builder

Server — the builder a user of this crate actually touches.

context

What a handler is given, and the gate in front of it.

dispatch

Routing a method name to the handler that serves it.

error

Errors the server API returns before anything reaches the wire.

live

What a server can still change once it is serving, and who hears about it.

log_gate

Which notifications/message records a session has asked to receive.

read

The JSON resources/read and prompts/get answer with.

result

The JSON a generated #[tool] handler answers with.

serve

The front door a consumer walks through.