homeassistant-mcp/src/index.ts

import { get_hass } from './hass/index.js';
import { LiteMCP } from 'litemcp';
import { z } from 'zod';
import { DomainSchema } from './schemas.js';

// Configuration
const HASS_HOST = process.env.HASS_HOST || 'http://192.168.178.63:8123';
const HASS_TOKEN = process.env.HASS_TOKEN;

interface CommandParams {
  command: string;
  entity_id: string;
  // Common parameters
  state?: string;
  // Light parameters
  brightness?: number;
  color_temp?: number;
  rgb_color?: [number, number, number];
  // Cover parameters
  position?: number;
  tilt_position?: number;
  // Climate parameters
  temperature?: number;
  target_temp_high?: number;
  target_temp_low?: number;
  hvac_mode?: string;
  fan_mode?: string;
  humidity?: number;
}

const commonCommands = ['turn_on', 'turn_off', 'toggle'] as const;
const coverCommands = [...commonCommands, 'open', 'close', 'stop', 'set_position', 'set_tilt_position'] as const;
const climateCommands = [...commonCommands, 'set_temperature', 'set_hvac_mode', 'set_fan_mode', 'set_humidity'] as const;

async function main() {
  const hass = await get_hass();

  // Create MCP server
  const server = new LiteMCP('home-assistant', '0.1.0');

  // Add the list devices tool
  server.addTool({
    name: 'list_devices',
    description: 'List all available Home Assistant devices',
    parameters: z.object({}),
    execute: async () => {
      try {
        const response = await fetch(`${HASS_HOST}/api/states`, {
          headers: {
            Authorization: `Bearer ${HASS_TOKEN}`,
            'Content-Type': 'application/json',
          },
        });

        if (!response.ok) {
          throw new Error(`Failed to fetch devices: ${response.statusText}`);
        }

        const states = await response.json();
        const devices = states.reduce((acc: any, state: any) => {
          const domain = state.entity_id.split('.')[0];
          if (!acc[domain]) {
            acc[domain] = [];
          }
          acc[domain].push({
            entity_id: state.entity_id,
            state: state.state,
            attributes: state.attributes,
          });
          return acc;
        }, {});

        return {
          success: true,
          devices,
        };
      } catch (error) {
        return {
          success: false,
          message: error instanceof Error ? error.message : 'Unknown error occurred',
        };
      }
    },
  });

  // Add the Home Assistant control tool
  server.addTool({
    name: 'control',
    description: 'Control Home Assistant devices and services',
    parameters: z.object({
      command: z.enum([...commonCommands, ...coverCommands, ...climateCommands])
        .describe('The command to execute'),
      entity_id: z.string().describe('The entity ID to control'),
      // Common parameters
      state: z.string().optional().describe('The desired state for the entity'),
      // Light parameters
      brightness: z.number().min(0).max(255).optional()
        .describe('Brightness level for lights (0-255)'),
      color_temp: z.number().optional()
        .describe('Color temperature for lights'),
      rgb_color: z.tuple([z.number(), z.number(), z.number()]).optional()
        .describe('RGB color values'),
      // Cover parameters
      position: z.number().min(0).max(100).optional()
        .describe('Position for covers (0-100)'),
      tilt_position: z.number().min(0).max(100).optional()
        .describe('Tilt position for covers (0-100)'),
      // Climate parameters
      temperature: z.number().optional()
        .describe('Target temperature for climate devices'),
      target_temp_high: z.number().optional()
        .describe('Target high temperature for climate devices'),
      target_temp_low: z.number().optional()
        .describe('Target low temperature for climate devices'),
      hvac_mode: z.enum(['off', 'heat', 'cool', 'heat_cool', 'auto', 'dry', 'fan_only']).optional()
        .describe('HVAC mode for climate devices'),
      fan_mode: z.enum(['auto', 'low', 'medium', 'high']).optional()
        .describe('Fan mode for climate devices'),
      humidity: z.number().min(0).max(100).optional()
        .describe('Target humidity for climate devices')
    }),
    execute: async (params: CommandParams) => {
      try {
        const domain = params.entity_id.split('.')[0] as keyof typeof DomainSchema.Values;

        if (!Object.values(DomainSchema.Values).includes(domain)) {
          throw new Error(`Unsupported domain: ${domain}`);
        }

        const service = params.command;
        const serviceData: Record<string, any> = {
          entity_id: params.entity_id
        };

        // Handle domain-specific parameters
        switch (domain) {
          case 'light':
            if (params.brightness !== undefined) {
              serviceData.brightness = params.brightness;
            }
            if (params.color_temp !== undefined) {
              serviceData.color_temp = params.color_temp;
            }
            if (params.rgb_color !== undefined) {
              serviceData.rgb_color = params.rgb_color;
            }
            break;

          case 'cover':
            if (service === 'set_position' && params.position !== undefined) {
              serviceData.position = params.position;
            }
            if (service === 'set_tilt_position' && params.tilt_position !== undefined) {
              serviceData.tilt_position = params.tilt_position;
            }
            break;

          case 'climate':
            if (service === 'set_temperature') {
              if (params.temperature !== undefined) {
                serviceData.temperature = params.temperature;
              }
              if (params.target_temp_high !== undefined) {
                serviceData.target_temp_high = params.target_temp_high;
              }
              if (params.target_temp_low !== undefined) {
                serviceData.target_temp_low = params.target_temp_low;
              }
            }
            if (service === 'set_hvac_mode' && params.hvac_mode !== undefined) {
              serviceData.hvac_mode = params.hvac_mode;
            }
            if (service === 'set_fan_mode' && params.fan_mode !== undefined) {
              serviceData.fan_mode = params.fan_mode;
            }
            if (service === 'set_humidity' && params.humidity !== undefined) {
              serviceData.humidity = params.humidity;
            }
            break;

          case 'switch':
          case 'contact':
            // These domains only support basic operations (turn_on, turn_off, toggle)
            break;

          default:
            throw new Error(`Unsupported operation for domain: ${domain}`);
        }

        // Call Home Assistant service
        try {
          const response = await fetch(`${HASS_HOST}/api/services/${domain}/${service}`, {
            method: 'POST',
            headers: {
              Authorization: `Bearer ${HASS_TOKEN}`,
              'Content-Type': 'application/json',
            },
            body: JSON.stringify(serviceData),
          });

          if (!response.ok) {
            throw new Error(`Failed to execute ${service} for ${params.entity_id}: ${response.statusText}`);
          }

          return {
            success: true,
            message: `Successfully executed ${service} for ${params.entity_id}`
          };
        } catch (error) {
          throw new Error(`Failed to execute ${service} for ${params.entity_id}: ${error instanceof Error ? error.message : 'Unknown error occurred'}`);
        }
      } catch (error) {
        return {
          success: false,
          message: error instanceof Error ? error.message : 'Unknown error occurred'
        };
      }
    }
  });

  // Start the server
  await server.start();
  console.log('MCP Server started');
}

main().catch(console.error);