Koharu privacy policy
Updated October 4, 2026
Short version: the Koharu Mac app reads token counts from the session logs on your Mac and sends nothing anywhere. The Koharu ChatGPT plugin never sees your messages; it stores a plan choice and a few numbers about chat length under pseudonymous keys, and deletes them on its own.
Who runs Koharu
Koharu is a Mac app and a ChatGPT plugin made by Carlos Lastres and operated by his company, インターナショナルデザイン合同会社 (International Design LLC), Shinjuku Dai-7 Hayama Bldg 3F, 1-36-2 Shinjuku, Shinjuku-ku, Tokyo 160-0022, Japan. For anything about your data, email carlos@intdesign.jp.
The Mac app
The app runs only on your Mac. It makes no network connections, has no account and no analytics, and sends nothing to us or anyone else.
- What it reads. The session logs that Claude Code writes in ~/.claude/projects and that Codex writes in ~/.codex/sessions. From each recent log it uses the token count of the latest reply, the model name, the name of the project folder and the file dates. Those logs also contain your conversations. Koharu reads past that text to find the numbers, and never keeps, shows or sends it.
- What it keeps. Your settings (her size, where she stands, bedtime and the other switches) in the app's own preferences on your Mac.
- Removing it. Quit Koharu from the menu bar and drag it to the Trash. If you turned on Open at login, turn it off in Settings first.
What the ChatGPT plugin receives
When ChatGPT calls Koharu, it sends only what her tools ask for, plus a few technical fields that ChatGPT adds to every plugin call:
- ChatGPT's estimate of how many tokens the conversation has used, as a single number.
- The plan and model mode you pick (for example Plus, Instant), or a custom budget number.
- An anonymized user id and an anonymized conversation id generated by ChatGPT. They do not contain your name, email or account details.
- Your locale and approximate location, which ChatGPT may attach to plugin calls. Koharu ignores them and does not store them.
Koharu never receives the text of your messages, files, images or ChatGPT's replies.
What the ChatGPT plugin stores and for how long
| Data | Why | Kept for |
|---|---|---|
| Your plan choice or custom budget | So she remembers your budget across chats | 180 days after you last set it |
| The highest chat length estimate, the point you last reset her, and whether a reset is waiting, per conversation | So she does not jump between tired and fresh inside one chat | 30 days after the last update |
Before anything is stored, the anonymized ids from ChatGPT are hashed with SHA-256 and only the hash is kept. That makes the records pseudonymous, not anonymous: someone who already had ChatGPT's id for you could compute the same hash, but nothing stored contains your name, email or account. Records expire automatically. Nothing else is kept.
Where the plugin runs
Koharu runs on Cloudflare Workers and stores her records in Cloudflare Workers KV. Cloudflare processes this data for us as a service provider and may do so in Japan, the United States and other countries. Koharu's Worker logs each request (time, path, status, errors and the calling IP address) for debugging and abuse prevention, and those logs are kept for up to 7 days. For plugin calls the calling IP belongs to ChatGPT's servers, not your device.
The Koharu widget inside ChatGPT loads its pictures and fonts directly from lastres.ai, so your browser or app sends those requests, with your IP address and user agent, to Cloudflare. They are handled like any web page request: Cloudflare may log them for security, and Koharu does not use them to identify or track you.
What Koharu does not do, in the app or the plugin
- No ads, no analytics and no tracking, in the app or inside the widget.
- No selling or sharing of data, and no use of it to train any model.
- No accounts and no sign in.
This website
The pages under lastres.ai/mods/ set no cookies and load no analytics. Fonts and images are served from lastres.ai itself. The rest of lastres.ai is covered by its own privacy policy.
Your choices
You can remove the Koharu plugin from ChatGPT at any time under Plugins. To have your records deleted sooner, email carlos@intdesign.jp with the approximate date you used her; since we cannot identify you from what is stored, we will clear all records from that period if needed. Reset in the widget clears her meter for the current chat right away.
Koharu is meant for users aged 13 and over.
Changes
If this policy changes, the date at the top changes too, and anything that changes what is stored will be described here before it takes effect.