gas_gemini_metadata.gs

function getMedadata_(url, parameters) {

   const SYSTEM_INSTRUCTIONS = `
    You are expert in parsing information (string, number, array, etc) from website
    Visit URL and parse listed parameters
    Return as simple text JSON format WITHOUT markdown
    
    Rules
    1. Dont add \`\`\`json into result

    Two Examples:

    First example:
    URL: https://www.csfd.cz/film/1481241-28-let-pote/prehled/
    Parameters: key (number), title (string),  duration (number), rating (number),
    Result:
    {
     "key (number)": 1,
     "title (string)": "title",
     "duration (number)": 120,
     "rating (number)": 77
    }

    Second example:
    URL: https://www.csfd.cz/film/9499-matrix/prehled/
    Parameters: rating (number), title (string)
    Result:
    {
     "rating (number)": 90,
     "title (string)": "Matrix"
    }

  `;

  
  let prompt = `
    URL: ${url}
    Parameters: ${parameters.join(",")}
    Result:    
  `;

  console.log(prompt)
  const systemInstruction = {
    parts: [{
      text: SYSTEM_INSTRUCTIONS
    }]
  };
  const payload = {
    systemInstruction,
    contents: [
      {
        role: 'user',
        parts: [
          {
            text: prompt
          },
        ]
      },
    ],
    "tools": [ { "url_context": {}} ],
    generationConfig: {
      temperature : 0,
      thinkingConfig: {
        thinkingBudget: 8096,
      },
      responseMimeType: 'text/plain',
    },
  };

  let data = gemini_('gemini-2.5-flash', payload)
  const content = data['candidates'][0]['content']['parts'][0]['text'];
  return JSON.parse(content)
}