How to save words to Koboshi from ChatGPT and Claude

Ask ChatGPT or Claude to save any word to Koboshi, and the word lands in your Koboshi vocabulary.

ChatGPT users: jump to ChatGPT. Claude users: jump to Claude.

Set it up once per app. The address is https://koboshi.app/mcp

ChatGPT

Needs a Plus, Pro, Business, Enterprise or Edu plan, on chatgpt.com.

1. Open Settings → Security and login and switch on Developer mode. Do this first: the + in step 2 only makes a Koboshi plugin once Developer mode is on.

   

2. Open Plugins and press + at the top right.

   

3. Fill in Name Koboshi, Server URL https://koboshi.app/mcp, Authentication OAuth.

   

4. Tick I understand and want to continue, then press Create.

   

5. Press Sign in with Koboshi, sign in, then press Approve.

   

6. Open a new chat and ask ChatGPT to save any word to Koboshi.

It worked if ChatGPT asks Allow ChatGPT to use Koboshi?

Claude

1. Open Settings → Connectors.

   

2. Press Add.

   

3. Type Koboshi as the name, paste https://koboshi.app/mcp, and press Continue.

   

4. Press Connect next to Koboshi, sign in, then press Approve.

   

   

5. In a chat, press + → Connectors. Koboshi is now on the list: switch it on.

Check: ask Claude to save any word to Koboshi.

If it does not work

• ChatGPT does not show a new Koboshi feature: open Plugins → Koboshi, press Refresh, then start a new chat.

  

• Claude does not use Koboshi, or misses a new Koboshi feature: open Settings → Connectors → Koboshi, press Disconnect, press Connect again, then open a new chat.

  

• Wrong Koboshi account: press Use a different account on the approval page.

• Still stuck: write to support@koboshi.app.

Using Claude Code or Codex? Connect them here. Steps checked on 2026-09-29.