homeassistant-mcp-bridge/custom_components/mcp_bridge/__init__.py

"""MCP Bridge integration for Home Assistant.

This integration provides services to expose filtered entities and scripts
to MCP (Model Context Protocol) servers for AI agent control.
"""
from __future__ import annotations

import logging
from typing import Any

from homeassistant.const import CONF_ENTITY_ID
from homeassistant.core import (
    HomeAssistant,
    ServiceCall,
    ServiceResponse,
    SupportsResponse,
)
from homeassistant.helpers import entity_registry as er
from homeassistant.helpers import area_registry as ar
from homeassistant.helpers.typing import ConfigType

_LOGGER = logging.getLogger(__name__)

DOMAIN = "mcp_bridge"
MCP_ACCESSIBLE_LABEL = "mcp_accessible"


async def async_setup(hass: HomeAssistant, config: ConfigType) -> bool:
    """Set up the MCP Bridge integration."""
    _LOGGER.info("Setting up MCP Bridge integration")

    async def get_exposed_entities(call: ServiceCall) -> ServiceResponse:
        """Return entities exposed to conversation."""
        entity_reg = er.async_get(hass)
        area_reg = ar.async_get(hass)

        exposed_entities: list[dict[str, Any]] = []

        for state in hass.states.async_all():
            entity_entry = entity_reg.async_get(state.entity_id)
            if not entity_entry:
                continue

            if not entity_entry.options.get("conversation", {}).get(
                "should_expose", False
            ):
                continue

            area_name = None
            if entity_entry.area_id:
                area = area_reg.async_get_area(entity_entry.area_id)
                if area:
                    area_name = area.name

            exposed_entities.append(
                {
                    "entity_id": state.entity_id,
                    "state": state.state,
                    "friendly_name": state.attributes.get(
                        "friendly_name", state.entity_id
                    ),
                    "area": area_name,
                    "domain": state.entity_id.split(".", 1)[0],
                    "device_class": state.attributes.get("device_class"),
                    "supported_features": state.attributes.get(
                        "supported_features", 0
                    ),
                    "last_changed": state.last_changed.isoformat(),
                    "last_updated": state.last_updated.isoformat(),
                    "attributes": dict(state.attributes),
                }
            )

        return ServiceResponse(
            {
                "entities": exposed_entities,
                "count": len(exposed_entities),
            }
        )

    async def get_exposed_scripts(call: ServiceCall) -> ServiceResponse:
        """Return scripts marked as MCP-accessible."""
        entity_reg = er.async_get(hass)
        exposed_scripts: list[dict[str, Any]] = []

        for entity_id in hass.states.async_entity_ids("script"):
            entity_entry = entity_reg.async_get(entity_id)
            if not entity_entry:
                continue

            if MCP_ACCESSIBLE_LABEL not in entity_entry.labels:
                continue

            state = hass.states.get(entity_id)
            if not state:
                continue

            exposed_scripts.append(
                {
                    "entity_id": entity_id,
                    "friendly_name": state.attributes.get(
                        "friendly_name", entity_id
                    ),
                    "description": state.attributes.get("description", ""),
                    "fields": state.attributes.get("fields", {}),
                }
            )

        return ServiceResponse(
            {
                "scripts": exposed_scripts,
                "count": len(exposed_scripts),
            }
        )

    async def get_entity_metadata(call: ServiceCall) -> ServiceResponse:
        """Return detailed metadata for a single entity."""
        entity_id = call.data.get(CONF_ENTITY_ID)

        if not entity_id:
            return ServiceResponse(
                {"error": "entity_id is required"},
                success=False,
            )

        entity_reg = er.async_get(hass)
        area_reg = ar.async_get(hass)

        state = hass.states.get(entity_id)
        if not state:
            return ServiceResponse(
                {"error": f"Entity {entity_id} not found"},
                success=False,
            )

        entity_entry = entity_reg.async_get(entity_id)

        area_name = None
        if entity_entry and entity_entry.area_id:
            area = area_reg.async_get_area(entity_entry.area_id)
            if area:
                area_name = area.name

        metadata: dict[str, Any] = {
            "entity_id": entity_id,
            "state": state.state,
            "friendly_name": state.attributes.get(
                "friendly_name", entity_id
            ),
            "area": area_name,
            "domain": entity_id.split(".", 1)[0],
            "device_class": state.attributes.get("device_class"),
            "supported_features": state.attributes.get(
                "supported_features", 0
            ),
            "last_changed": state.last_changed.isoformat(),
            "last_updated": state.last_updated.isoformat(),
            "attributes": dict(state.attributes),
        }

        if entity_entry:
            metadata["labels"] = list(entity_entry.labels)
            metadata["is_exposed_to_conversation"] = entity_entry.options.get(
                "conversation", {}
            ).get("should_expose", False)

        return ServiceResponse(metadata)

    hass.services.async_register(
        DOMAIN,
        "get_exposed_entities",
        get_exposed_entities,
        supports_response=SupportsResponse.ONLY,
    )

    hass.services.async_register(
        DOMAIN,
        "get_exposed_scripts",
        get_exposed_scripts,
        supports_response=SupportsResponse.ONLY,
    )

    hass.services.async_register(
        DOMAIN,
        "get_entity_metadata",
        get_entity_metadata,
        supports_response=SupportsResponse.ONLY,
    )

    _LOGGER.info("MCP Bridge services registered successfully")
    return True