.. index:: single: mcp_server_spec_protocol
.. _mcp_server_spec_protocol/0:

.. rst-class:: right

**protocol**

``mcp_server_spec_protocol``
============================

Protocol for MCP server spec (aka data layer) handlers independent of transport. A handler validates and dispatches JSON-RPC messages and returns abstract outcomes that a transport (stdio or Streamable HTTP) renders to the wire.

| **Availability:** 
|    ``logtalk_load(mcp_server(loader))``

| **Author:** Paulo Moura
| **Version:** 1:0:0
| **Date:** 2026-08-31

| **Compilation flags:**
|    ``static``


| **Dependencies:**
|   (none)


| **Remarks:**
|    (none)

| **Inherited public predicates:**
|    (none)

.. contents::
   :local:
   :backlinks: top

Public predicates
-----------------

.. index:: spec/1
.. _mcp_server_spec_protocol/0::spec/1:

``spec/1``
^^^^^^^^^^

MCP server spec implemented by this handler (e.g. ``'2025-06-18'`` or ``'2026-07-28'``).

| **Compilation flags:**
|    ``static``

| **Template:**
|    ``spec(Version)``
| **Mode and number of proofs:**
|    ``spec(-atom)`` - ``one``


------------

.. index:: prepare/2
.. _mcp_server_spec_protocol/0::prepare/2:

``prepare/2``
^^^^^^^^^^^^^

Initializes handler state for ``Application`` with merged ``Options``. Does not open any transport.

| **Compilation flags:**
|    ``static``

| **Template:**
|    ``prepare(Application,Options)``
| **Mode and number of proofs:**
|    ``prepare(+object_identifier,+list)`` - ``one_or_error``

| **Exceptions:**
|    ``Options`` is a variable:
|        ``instantiation_error``
|    ``Options`` is neither a variable nor a list:
|        ``type_error(list,Options)``
|    An element ``Option`` of the list ``Options`` is a variable:
|        ``instantiation_error``
|    An element ``Option`` of the list ``Options`` is neither a variable nor a compound term:
|        ``type_error(compound,Option)``
|    An element ``Option`` of the list ``Options`` is a compound term but not a valid option:
|        ``domain_error(option,Option)``


------------

.. index:: handle_message/3
.. _mcp_server_spec_protocol/0::handle_message/3:

``handle_message/3``
^^^^^^^^^^^^^^^^^^^^

Handles one JSON-RPC Message under Options and returns an Outcome for the transport to render. Outcomes include ``reply(JsonRpcTerm)``, ``accepted``, ``no_reply``, and transport-agnostic error replies already encoded as JSON-RPC error objects inside ``reply/1``.

| **Compilation flags:**
|    ``static``

| **Template:**
|    ``handle_message(Message,Options,Outcome)``
| **Mode and number of proofs:**
|    ``handle_message(+nonvar,+list,-nonvar)`` - ``one``


------------

.. index:: notify/1
.. _mcp_server_spec_protocol/0::notify/1:

``notify/1``
^^^^^^^^^^^^

Publishes an application event. Transports that support server-initiated notifications deliver it; others may ignore it.

| **Compilation flags:**
|    ``static``

| **Template:**
|    ``notify(Event)``
| **Mode and number of proofs:**
|    ``notify(+compound)`` - ``zero_or_one``


------------

.. index:: cleanup/0
.. _mcp_server_spec_protocol/0::cleanup/0:

``cleanup/0``
^^^^^^^^^^^^^

Releases handler-owned dynamic state.

| **Compilation flags:**
|    ``static``

| **Mode and number of proofs:**
|    ``cleanup`` - ``one``


------------

Protected predicates
--------------------

(none)

Private predicates
------------------

(none)

Operators
---------

(none)