Claude-to-Gemini MCP Server

Instructions

Implementation Reference

• index.js:287-351 (handler)

  Executes the 'generate_image_imagen' tool by calling the Imagen 4 REST API, handling the response, saving images to disk, and returning text and image content.

  if (name === "generate_image_imagen") {
    const { prompt, numberOfImages = 1 } = args;
  
    // REST API를 사용하여 Imagen 4 호출
    const response = await fetch(
      `https://generativelanguage.googleapis.com/v1beta/models/imagen-4.0-generate-001:predict`,
      {
        method: "POST",
        headers: {
          "x-goog-api-key": apiKey,
          "Content-Type": "application/json",
        },
        body: JSON.stringify({
          instances: [{ prompt: prompt }],
          parameters: {
            sampleCount: numberOfImages,
          },
        }),
      }
    );
  
    if (!response.ok) {
      const errorText = await response.text();
      throw new Error(`Imagen API error: ${response.status} - ${errorText}`);
    }
  
    const result = await response.json();
  
    // predictions 배열 확인 (실제 API 응답 구조)
    if (!result.predictions || result.predictions.length === 0) {
      throw new Error(`No images were generated. Response: ${JSON.stringify(result)}`);
    }
  
    // 이미지 저장
    const outputDir = join(__dirname, "generated_images");
    await mkdir(outputDir, { recursive: true });
  
    const timestamp = new Date().toISOString().replace(/[:.]/g, "-");
    const savedPaths = [];
  
    for (let i = 0; i < result.predictions.length; i++) {
      const img = result.predictions[i];
      const filename = `imagen_${timestamp}_${i + 1}.png`;
      const filepath = join(outputDir, filename);
  
      // bytesBase64Encoded 필드 사용
      const buffer = Buffer.from(img.bytesBase64Encoded, "base64");
      await writeFile(filepath, buffer);
      savedPaths.push(filepath);
    }
  
    return {
      content: [
        {
          type: "text",
          text: `[Imagen 4]\n\nGenerated ${result.predictions.length} image(s) for: "${prompt}"\n\nSaved to:\n${savedPaths.map(p => `- ${p}`).join("\n")}\n\nNote: All images include SynthID watermark for authenticity.`,
        },
        ...result.predictions.map((img) => ({
          type: "image",
          data: img.bytesBase64Encoded,
          mimeType: img.mimeType || "image/png",
        })),
      ],
    };
  }

• index.js:119-142 (registration)

  Registers the 'generate_image_imagen' tool in the ListTools response, defining its name, description, and input schema.

  {
    name: "generate_image_imagen",
    description:
      "Generate images using Imagen 4. Best for photorealistic quality, high-resolution outputs, and professional branding. Paid service.",
    inputSchema: {
      type: "object",
      properties: {
        prompt: {
          type: "string",
          description:
            "Description of the image to generate (in English, max 480 tokens)",
        },
        numberOfImages: {
          type: "number",
          description:
            "Number of images to generate (1-4, default: 1)",
          default: 1,
          minimum: 1,
          maximum: 4,
        },
      },
      required: ["prompt"],
    },
  },

• index.js:123-141 (schema)

  Defines the input schema for the 'generate_image_imagen' tool, specifying prompt and optional numberOfImages parameters.

  inputSchema: {
    type: "object",
    properties: {
      prompt: {
        type: "string",
        description:
          "Description of the image to generate (in English, max 480 tokens)",
      },
      numberOfImages: {
        type: "number",
        description:
          "Number of images to generate (1-4, default: 1)",
        default: 1,
        minimum: 1,
        maximum: 4,
      },
    },
    required: ["prompt"],
  },