Promptline: your ChatGPT and Gemini, on autopilot.
Promptline runs prompts in your own ChatGPT and Gemini accounts for other apps and AI agents, then hands back the reply and any images. No API key, no credits, no fee per prompt.
Windows 10 or later · Android 8.0 or later · Free, with no account
How it works
Promptline is a small browser with a queue. Apps add prompts; Promptline types them into ChatGPT or Gemini, waits for the answer, and returns it.
Install
Install Promptline on the computer or phone where you use KDPify or your own tools.
Sign in once
Open ChatGPT and Gemini inside Promptline and sign in. Free accounts work. Promptline remembers you.
Queue prompts
KDPify, a script or an AI agent sends prompts, with images if you like. They run one after another at a steady pace.
Get the results
The reply text and every generated image come back to the app that asked, ready to use.
What you can use it for
Draw a whole book in KDPify
Choose Promptline as your drawing method and every page of the book is drawn by ChatGPT or Gemini, one after another, while you do something else.
Give your AI agent ChatGPT and Gemini
Copy the AI skill from the app and your coding agent can ask ChatGPT or Gemini for images, second opinions or long answers, using your accounts.
Batch work from your own scripts
Queue dozens of prompts from the command line or the local HTTP API, keep related prompts in the same chat, and collect every image in a folder.
For developers
Promptline listens on http://127.0.0.1:7777, on the same device only. Any app or agent on that device can use it.
Command line (Windows)
# Waits, then prints the reply promptline add -p chatgpt "Write a book description for…" # Generate an image and save it promptline add -p chatgpt --tool "Create image" \ --save-images out "A coloring page of a fox" # Keep a series in the same chat promptline add -p gemini -s book-42 "Chapter 1…"
HTTP API (Windows and Android)
# Queue a job POST /api/jobs { "provider": "chatgpt", "prompt": "A coloring page of a fox", "tool": "Create image" } # Wait for it, then read the text and images GET /api/jobs/{id}/wait?timeout=600000
Questions
Is Promptline really free?
Yes. Promptline is free and needs no account. It uses your own ChatGPT and Gemini accounts, so what you can generate depends on those accounts' limits.
Do I need an API key?
No. Promptline uses the ChatGPT and Gemini websites you are signed in to, not their paid APIs.
Where do my prompts go?
Straight from your device to ChatGPT or Gemini. Promptline has no server of its own and sends nothing to KDPify. Your jobs, images and sign-ins stay on your device.
Do I need KDPify to use it?
No. Promptline works on its own with any app, script or AI agent. KDPify is one of the apps that can use it.
How do I use it with KDPify?
Install Promptline on the same device as KDPify, sign in to ChatGPT or Gemini in Promptline, then choose Promptline as the drawing method in KDPify's settings (or when you first open the app on your phone).
Will it send too many prompts?
Promptline waits a few seconds between prompts to the same site by default, and you can make the gap longer in its settings.