Connect ChatGPT, Codex, or another AI assistant so it can search cards, understand your decks, manage your collection, and prepare deck improvements for you to review.
Set Name to Cartheca and Type to Streamable HTTP. Do not choose STDIO.
3
Enter the address
URL
https://your-cartheca-host/mcp
Leave the bearer-token environment variable and custom headers empty.
4
Sign in and approve
Save the connection. When Cartheca opens, sign in and choose Connect assistant.
5
Start a new conversation
Open the tools menu, enable Cartheca, and begin with the read-only test below.
ChatGPT
OAuth · No key required
Add Cartheca as an MCP plugin, then sign in when ChatGPT opens the secure connection window.
Where plugins are located
Settings→Security and login→Developer mode→Plugins
Developer mode availability can depend on your ChatGPT account and workspace policy.
1
Enable Developer mode
In ChatGPT, open Settings → Security and login, then turn on Developer mode.
2
Add Cartheca
Open Plugins, choose the plus button, and enter Cartheca as the name.
MCP address
https://your-cartheca-host/mcp
3
Sign in and approve
Create the connection. ChatGPT will open Cartheca; sign in if needed, review the access request, and choose Connect assistant.
4
Start a conversation
Open a new conversation, select Cartheca from the tools menu, and begin with the read-only test below.
Claude Code
Terminal setup
Claude Code supports a hosted MCP address with a custom request header.
1
Create your private key
Create and copy a key from Account & API keys. Choose what the key may do while creating it — an assistant only ever gets the permissions you tick.
2
Add the remote server
Open Claude Code’s MCP setup and add a remote HTTP server named Cartheca.
Server URL
https://your-cartheca-host/mcp
Header
X-API-Key
Value
Paste your private key
3
Confirm the tools
Use Claude Code’s /mcp command. Cartheca should appear as connected with its deck and collection tools.
4
Start with a read-only request
Ask Claude Code to list your decks without making changes.
Cartheca supports OAuth, so an OAuth-capable client can connect without a key at all. Claude’s hosted “custom connector” path has not been verified against Cartheca yet, so this key-based Claude Code setup is the one we document.
Gemini API
Developer integration
This option is for an app or agent built with the Gemini API. It is not a setting in the consumer Gemini chat app.
1
Create both keys
Create a Cartheca key from Account & API keys and a Gemini API key from Google AI Studio.
2
Register Cartheca as an MCP server
In your Gemini agent’s MCP server configuration, use:
Type
mcp_server
Name
cartheca
URL
https://your-cartheca-host/mcp
Header
X-API-Key: your private key
3
Allow the tools
Allow all Cartheca tools, or select only the read and write tools your agent needs.
4
Run a read-only test
Ask the agent to list the decks in your Cartheca library before allowing it to make changes.
First conversation
Make sure it works
Start a new conversation with Cartheca enabled, then try:
Show me the decks in my Cartheca library, then summarize the first one. Do not make any changes.
If the assistant lists your decks, the connection is ready.
You remain in control
What happens when AI suggests a change?
1. The AI prepares a proposal
Your live deck is not changed.
→2. You review it in Deck Builder
Keep, uncheck, or reject any suggestion.
→3. You approve the final list
Only then does Cartheca update the deck.
End an assistant’s access from Account & API keys, where Connected assistants lists every OAuth connection with what it may do and when it last used it. Disconnecting stops that connection at once, including its ability to refresh, and does not depend on the assistant cooperating. Legacy API keys are revoked from the same page, and changing your password revokes every connection and key you hold.
If it does not connect
Check these four things
Type: Streamable HTTP is selected, not STDIO.
Address: the URL ends in /mcp and begins with https://.
Sign-in: allow the Cartheca sign-in window and approve the connection.
New conversation: after saving or changing the connection, start a new chat before testing it.
If authorization was interrupted, remove the incomplete connection and add the MCP address again.
