Make and study flashcards in Claude and ChatGPT

Connect NextLang to your AI assistant once and ask for decks, files and vocabulary reviews in plain words. It works through MCP (Model Context Protocol), the standard way assistants use outside apps.

Server address

https://www.nextlang.co/api/mcp

What you can ask

Study

SayWhat happensCost
“Quiz me on my Spanish words”The assistant asks you the words that are due, checks your answers and saves the results to your review schedule.Free
“What languages am I learning?”Lists your dictionaries with their language pairs.Free

Vocabulary

SayWhat happensCost
“Save "castle" to my Spanish vocabulary”Adds the word and its translation to your vocabulary.Free
“Do I already have "castle"?”Searches your vocabulary, accents or not.Free

Decks

SayWhat happensCost
“Make an Anki deck of 20 airport words, I'm learning Spanish”NextLang writes the deck with its own generator and saves it to your account: translations, your CEFR level, no duplicates.1 credit
“Turn this word list into a Mochi deck”Saves the cards you pasted or wrote together in the chat as a deck.Free
“Add 10 more cards to it”Extends the deck with new cards that are not in it yet.1 credit
“Show me the cards of my kitchen deck”Finds the deck by name and shows its cards, with a link.Free
“How many Spanish decks do I have?”Counts and lists your decks, with links.Free

Files

SayWhat happensCost
“Give me the .apkg for this deck”A download link for the Anki (.apkg) or Mochi (.mochi) file, with pronunciation audio when it can be made. The link works for one hour.Premium

Account

SayWhat happensCost
“How many credits do I have?”Your balance and, if it is low, when free credits return.Free

Connect in a minute

Claude

  1. Open Settings, then Connectors.
  2. Choose Add custom connector, name it NextLang and paste the server address above.
  3. Press Connect, sign in to NextLang with Google and allow access.
  4. In a chat, make sure NextLang is switched on in the tools menu, then just ask.

ChatGPT

  1. Open Settings, then Apps & Connectors, and turn on Developer mode under Advanced settings.
  2. Create a connector, name it NextLang, paste the server address above and choose OAuth.
  3. Sign in to NextLang with Google and allow access.
  4. In a chat, pick NextLang from the tools menu, then just ask.

For developer tools

Claude Code

claude mcp add --transport http nextlang https://www.nextlang.co/api/mcp

Codex CLI

codex mcp add nextlang --url https://www.nextlang.co/api/mcp && codex mcp login nextlang

Codex may look in your files first. Start a request with "Using NextLang, ..." or add a line about NextLang to your AGENTS.md.

What's free and what costs credits

  • Studying, your vocabulary, lists and saving cards you already have are free.
  • Generating a deck or adding cards to one costs 1 credit, exactly as on the website.
  • Anki and Mochi files are part of Premium, which any credit pack unlocks.
  • NextLang asks your assistant to confirm before spending a credit unless you asked for the deck outright, Claude and ChatGPT ask for your approval before a tool runs unless you turned that off, and every paid answer shows what is left.

Why not just ask the chatbot for cards?

Real files, not text to copy

A chatbot can write cards, but it cannot hand you an Anki package. NextLang builds a real .apkg or .mochi file, with pronunciation audio inside when it can be made.

Cards that fit your level

Decks follow your CEFR level and drop repeated words, with the same generator the website uses.

It remembers between chats

Your decks and vocabulary live in your NextLang account, and reviews follow a spaced repetition schedule, so tomorrow's chat knows what is due.

Four apps, nothing to install

Anki, Quizlet, Mochi and Brainscape, from the Claude or ChatGPT app on your phone or computer. No desktop app has to be running.

Privacy and control

  • The assistant only sees what it asks for while you use it: the words in your vocabulary, the cards of your decks, your deck names and your credit balance.
  • It signs in through your NextLang account and never sees your Google password.
  • Disconnect at any time in your account, under Connected apps: access stops at once, and a file link already given out expires within the hour.
  • Details are in the privacy policy.

FAQ

Questions about the connector

What people ask before connecting NextLang to their assistant.

Does it work on my phone?

Yes. Once connected in Claude or ChatGPT, the connector works in their phone apps too, because NextLang runs on our servers, not on your device.

Which assistants can I use?

Claude (web, desktop and mobile) and ChatGPT with Developer mode, plus developer tools such as Claude Code and Codex CLI. Any assistant that supports remote MCP servers with sign-in can connect to the same address.

Do I need Anki installed?

No. Nothing has to run on your computer. Decks are saved in your NextLang account, and Premium members get a download link for the Anki or Mochi file to import whenever they like.

Is my data used to train AI models?

NextLang does not train models on your data. What the assistant does with the answers it receives is governed by its own service, so check the settings of Claude or ChatGPT.

What does it cost?

Connecting is free. Studying, your vocabulary and saving your own cards are free; generating or extending a deck costs 1 credit, the same as on the website; files are part of Premium. See credit packs

The file link stopped working. What now?

Download links last one hour. Ask your assistant for the file again and it will give you a fresh link.

Can it make cloze (fill-in-the-blank) cards?

Not from the chat yet: the connector makes basic front and back cards. Cloze decks for Anki and Mochi are made on the website. Open the Anki generator

How do I disconnect?

Open your account, find Connected apps and press Disconnect. The assistant loses access immediately; a file link it already gave you expires within the hour.

For developers: tool reference

Remote MCP server at https://www.nextlang.co/api/mcp over Streamable HTTP, OAuth 2.1 with Google sign-in, scope account. Every tool acts only on the signed-in account; argument schemas come from the server's tool list.

ToolWhat it doesAccessCost
list_due_wordsWords due for review in a dictionary, or every dictionary with its language pairReadFree
record_reviewSaves how each reviewed word went to the review scheduleWriteFree
search_vocabularyLooks a word up in your vocabularyReadFree
add_vocabulary_itemsAdds words with translations to your vocabularyWriteFree
generate_deckGenerates a deck for Anki, Quizlet, Mochi or BrainscapeWrite1 credit
save_deckSaves cards you provided as a deckWriteFree
expand_deckAdds new cards to one of your decksWrite1 credit
list_decksLists and counts your decks, by language or by nameReadFree
get_deckReturns the cards of one deckReadFree
get_deck_fileA one-hour download link to the .apkg or .mochi fileReadPremium
get_creditsYour credit balance, premium status and free-credit renewalReadFree