Conversion Tools - Gemini CLI Extension

Conversion Tools extension for Gemini CLI. Convert 140+ file formats directly in your terminal - no browser tabs, no copy-pasting. Or build a custom converter from a plain-language description when no standard one fits.

Part of the Conversion Tools agent integrations (Claude Code, Cursor, Codex, Grok, Gemini, plus the ctio CLI).

Install

gemini extensions install https://github.com/conversiontools/gemini-extension

Update

Pull the latest version (recommended periodically - new converters and fixes ship regularly):

gemini extensions update conversiontools

Or update every installed extension:

gemini extensions update --all

Usage

Once installed, just ask Gemini to convert files:

Convert data.json to Excel

Transform this XML file to CSV

Convert report.pdf to a Word document

Available Tools

Tool Description
convert_file Convert a file from one format to another
list_converters List available converters by category
find_converter Find the best converter for specific formats
get_converter_info Get detailed info about a converter
request_upload_url Get upload URL for large files (over 5MB)
auth_status Check authentication status
auth_login Login via OAuth
auth_logout Logout and clear credentials
studio_create_converter Build a custom converter: create it + attach the input file
studio_chat Describe the transformation in plain language; the converter is built
studio_run Run the built converter on the file
studio_run_status Poll the run until it finishes
studio_download_result Download the result
studio_list_converters List your previously built converters (to reuse one instead of rebuilding)
studio_get_converter Inspect a converter's details and check it's ready to run
studio_attach_file Attach a new file to an existing converter and re-run its built logic

Supported Conversions

140+ conversion types including:

  • Documents: Word, PowerPoint, Excel, Markdown, ODS to/from PDF, HTML, Text, LaTeX
  • Data: JSON, CSV, XML, YAML, Parquet, JSONL, BSON, Excel - with validators and formatters
  • Images: PNG, JPG, WebP, AVIF, HEIC, JXL (JPEG XL), SVG, BMP, TIFF, GIF
  • PDF: Extract to Word, Excel, CSV, Text, HTML, Images (JPG, PNG, SVG, TIFF), EPUB
  • Audio: MP3, WAV, FLAC - plus AI text-to-speech and speech-to-text
  • Video: MP4, MOV, MKV, AVI - plus audio extraction
  • E-books: EPUB, MOBI, AZW, AZW3, FB2, FBZ, PDF
  • OCR: Extract text from images and scanned PDFs - output as Text or searchable PDF
  • AI-powered: Smart extraction from complex documents, subtitle translation, TTS, STT
  • Subtitles: SRT, VTT, ASS - bidirectional conversions
  • Web: Website screenshots (URL to PDF, JPG, PNG)
  • Custom (AI Studio): describe a transformation in plain language and have a reusable converter built, run, and returned - for when no standard converter fits

Authentication

On first use, you will be prompted to authenticate via OAuth. This opens a browser window to log in to your Conversion Tools account.

Free accounts get 100 conversions per month (10 per day). Paid plans available at conversiontools.io/pricing.

Examples

Convert JSON to Excel

I have a data.json file with an array of objects. Convert it to Excel.

Extract data from PDF

Extract the table from invoice.pdf to CSV

Links

License

MIT