Catai

catai is a CLI tool for concatenating multiple files into a single output suitable for LLM (Large Language Model) contexts. It intelligently handles file inclusion/exclusion, large files, and can copy the result to your clipboard.

catai deno.json a.ts

📂 Included Files:
├── 📄 a.ts
└── 📄 deno.json

📊 Summary:
   Files: 2
   Size: 299B

-- file: deno.json --
{
  "name": "@sigma/catai",
  "version": "1.0.1",
  "exports": "./catai.ts",
  "license": "MIT",
  "imports": {
    "@sigma/parse": "jsr:@sigma/parse@^0.50.0",
    "@std/fs": "jsr:@std/fs@^1.0.20",
    "@std/path": "jsr:@std/path@^1.1.3"
  }
}

-- file: a.ts --
console.log(4)

---

Features

• Concatenate text files from multiple directories.
• Filter files using include/exclude glob patterns.
• Automatically skip binary files (images, audio, video, archives, etc.).
• Warns for large files and allows interactive decisions.
• Shows a directory tree of included files.
• Supports copying output to clipboard (Wayland/X11).
• Optional output file writing.

---

Installation

deno install -Afg --name catai jsr:@sigma/catai

You can also run with bun using

bunx rjsr @sigma/catai

---

Usage

Basic usage:

catai [options] <paths...>

Options

Option	Description
--output <file>	Write concatenated result to a file instead of stdout
--include <patterns>	Include only files matching these glob patterns (e.g., *.ts, **/*.md)
--exclude <patterns>	Exclude files matching these glob patterns (e.g., **/*.test.js)
--maxSize <size>	Max file size before warning (default: 100k, e.g., 1mb, 500k)
--yes	Skip prompts for large files and include them automatically
--copy	Copy the result to the clipboard automatically

Example

Concatenate all .ts and .md files in the src directory:

catai --include "**/*.ts" "**/*.md" src

Output to a file and copy to clipboard:

catai --output all_files.txt --copy src

---

Supported File Types

catai automatically skips binary files including:

• Images: .png, .jpg, .gif, .webp, .bmp, .ico
• Audio/Video: .mp3, .mp4, .wav, .avi, .mov, .mkv
• Archives: .zip, .tar, .gz, .rar, .7z
• Executables/Libraries: .exe, .dll, .so, .dylib, .bin
• Fonts: .woff, .woff2, .ttf, .eot, .otf
• PDFs: .pdf

---

Tips:

This allows you to paste as file, llm chat will recognize this as file instead of text and present it nicly in the UI (somehow there doesn't seem to be a better way on linux other then spawning the file manager)

catai file1 file2 >/tmp/o.txt && nautilus /tmp/o.txt # then copy the file from nautilus

I even have this convenience function in fish:

function nn
    set tmp /tmp/nn.txt
    
    # Test whether stdin has data
    if test -t 0
        # No stdin → use wl-paste
        wl-paste > $tmp
    else
        # Stdin provided → write stdin to file
        cat - > $tmp
    end
    
    nautilus $tmp
end

---

License

MIT License