LIFX MCP Server

Instructions

Implementation Reference

• src/index.ts:234-247 (registration)

  Registration of the activate_scene tool in the ListToolsRequestSchema handler. Includes the tool name, description, and JSON input schema defining parameters: token (required), scene_uuid (required), duration (optional), fast (optional).

  {
    name: "activate_scene",
    description: "Activate a scene",
    inputSchema: {
      type: "object",
      properties: {
        token: { type: "string", description: "LIFX API token" },
        scene_uuid: { type: "string", description: "Scene UUID" },
        duration: { type: "number", minimum: 0, description: "Duration in seconds" },
        fast: { type: "boolean", description: "Fast mode (skip confirmation)" },
      },
      required: ["token", "scene_uuid"],
    },
  },

• src/index.ts:437-463 (handler)

  The core handler logic for the activate_scene tool within the CallToolRequestSchema switch statement. Extracts arguments, builds the request body from optional duration and fast params, invokes makeLIFXRequest to PUT /scenes/scene_id:{scene_uuid}/activate, and returns success message with API response.

  case "activate_scene": {
    const { token, scene_uuid, duration, fast } = args as {
      token: string;
      scene_uuid: string;
      duration?: number;
      fast?: boolean;
    };
  
    const body = Object.fromEntries(
      Object.entries({ duration, fast }).filter(([_, value]) => value !== undefined)
    );
  
    const result = await makeLIFXRequest(`/scenes/scene_id:${scene_uuid}/activate`, {
      method: "PUT",
      body,
      token,
    });
  
    return {
      content: [
        {
          type: "text",
          text: `Scene activated successfully. ${JSON.stringify(result, null, 2)}`,
        },
      ],
    };
  }

• src/index.ts:72-114 (helper)

  Shared helper function makeLIFXRequest used by the activate_scene handler (and all other tools) to perform authenticated HTTP requests to the LIFX API, handling headers, JSON body, error checking, and response parsing.

  async function makeLIFXRequest(
    endpoint: string,
    options: {
      method?: string;
      body?: any;
      token: string;
    }
  ): Promise<any> {
    const { method = "GET", body, token } = options;
    
    const url = `${LIFX_API_BASE}${endpoint}`;
    const headers: Record<string, string> = {
      "Authorization": `Bearer ${token}`,
      "User-Agent": USER_AGENT,
    };
  
    if (body && (method === "POST" || method === "PUT")) {
      headers["Content-Type"] = "application/json";
    }
  
    try {
      const response = await fetch(url, {
        method,
        headers,
        body: body ? JSON.stringify(body) : undefined,
      });
  
      if (!response.ok) {
        const errorText = await response.text();
        throw new Error(`LIFX API error: ${response.status} ${response.statusText} - ${errorText}`);
      }
  
      // Some endpoints return empty responses
      const contentType = response.headers.get("content-type");
      if (contentType?.includes("application/json")) {
        return await response.json();
      }
      
      return await response.text();
    } catch (error) {
      throw new Error(`Failed to make LIFX API request: ${error instanceof Error ? error.message : String(error)}`);
    }
  }

• src/index.ts:51-69 (schema)

  TypeScript interface definition for LIFXScene, used in related tools like list_scenes, providing structure for scene data relevant to activate_scene.

  interface LIFXScene {
    uuid: string;
    name: string;
    account: {
      uuid: string;
    };
    states: Array<{
      selector: string;
      power: string;
      brightness: number;
      color: {
        hue: number;
        saturation: number;
        kelvin: number;
      };
    }>;
    created_at: number;
    updated_at: number;
  }