This script is a Google Action that renames PDF files in a designated folder based on their content. It leverages Google Drive OCR and OpenAI Complete API. To use this script, you will need an OpenAI token and to add the Drive API Service. Additionally, it's recommended to update the GPT prompt to make it more adaptable to different use cases.

auto_rename_pdf_using_ocr_and_gpt.gs

const openAiApiKey = '***'
const openAiCompletionApiUrl = 'https://api.openai.com/v1/completions';
const additionalPromptCharsLimit = 1600;

function myFunction() {
    const idOfFolderContainingPdfs = '{ADD ID HERE}'
    const idOfDestinationFolder = '{ADD ID HERE}'

    const SourceFolder = DriveApp.getFolderById(idOfFolderContainingPdfs)
    const DestinationFolder = DriveApp.getFolderById(idOfDestinationFolder)

    const Files = SourceFolder.getFiles();

    while(Files.hasNext()) {
        const file = Files.next()
        const fileName = file.getName()

        Logger.log('Found file ' + fileName)

        const newFileName = createPdfFileName(file);

        DestinationFolder.addFile(file.makeCopy(newFileName));
        // file.setTrashed(true)

        Logger.log(newFileName + " created")
    }
}

function createPdfFileName(pdfDocument) {
    
    let text = convertPDFToText(pdfDocument, 'en')

    text = text.replace(/[\n\r\t\s]+/g, ' ')

    if (text.length > additionalPromptCharsLimit) {
        text = text.slice(0, additionalPromptCharsLimit);
    }

    Logger.log("OCR (first " + additionalPromptCharsLimit + " chars): " + text)

    const title = gptCompleteTitleByText(text)
    
    return `${title}.pdf`
}


function gptCompleteTitleByText(text) {

    const prompt = 'A title should contain the short topic of the text, the date (year is sufficient) and' 
        + 'the company name. If Alice or Bob or both are mentioned, it should be in the title.\n\n'
        + `Text: "${text.trim()}"\n\n`
        + 'Title:'

    const options = {
        'method': 'POST',
        'headers': {
            'Authorization': `Bearer ${openAiApiKey}`,
            'Content-Type': 'application/json'
        },
        'payload': JSON.stringify({
            'model': 'text-davinci-003',
            'prompt': prompt,
            'max_tokens': 90,
            'temperature': 0
        })
    };

    const response = UrlFetchApp.fetch(openAiCompletionApiUrl, options);
    const responseData = JSON.parse(response.getContentText());

    if (responseData && responseData.choices && responseData.choices.length > 0) {
        let title = responseData.choices[0].text;
        title = title.trim().replace(/^['"]|['"]$/g, '')

        Logger.log('GPT title: ' + title)

        return title;
    }

    Logger.log('Failed to generate text:', response.getContentText());
}


function convertPDFToText(pdfDocument, language) {

    const { id } = Drive.Files.insert(
        {
            title: pdfDocument.getName().replace(/\.pdf$/, ''),
            mimeType: pdfDocument.getMimeType() || 'application/pdf',
        },
        pdfDocument.getBlob(),
        {
            ocr: true,
            ocrLanguage: language,
            fields: 'id',
        }
    );

    const textContent = DocumentApp.openById(id).getBody().getText();
    DriveApp.getFileById(id).setTrashed(true);

    return textContent;
}