Connect docs · Scripts

Scripts and other clients: a key

For a script, or a client that can't sign in: a key, sent as a header. It works like an app you allowed, until you revoke it.

Steps

Sign in on app.3v3.dev/connect, and under Scripts and other clients make a key. It is shown once: keep it like a password, never in a chat or a repository.
Send it as Authorization: Bearer 3v3_dev_… with every message. MCP is JSON-RPC 2.0 over HTTP, one message per POST:
```
curl -s https://mcp.3v3.dev \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $V3_KEY" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'
```
The answer lists the tools. Any MCP client that takes a URL and a header works the same way.
Revoke a key on the Connect page when you're done with it: it stops at once.

Limits

Each key may send 120 messages a minute and make 50 boards a day through MCP; your plan has its own limits on layers and boards a month. A key can't touch your account's own controls (your password, keys or plan).

If it stops

What 3V3 says, word for word, and what to do.

When	3V3 says	Do this
Your app says it needs to sign in, or 401	This endpoint needs your API key: send it as “Authorization: Bearer 3v3_dev_…”. Make one on the Connect an agent page (/connect).	An app that signs in does this for you: let it open 3V3's page. A script sends a key.
You disconnected the app	That app was disconnected from your 3V3 account. Connect it again to carry on.	Connect it again (the same steps); Disconnect on the Connect page did exactly this.
The sign-in ran out	That sign-in has expired; your app gets a new one on its own.	Normally the app refreshes it by itself. If it keeps saying so, sign in again from the app.
A revoked key	That key was revoked. Make a new one at POST /api/keys.	Make a new key on app.3v3.dev/connect and put it where the old one was.
Too fast	Slow down: this key has sent 120 messages in the last minute, and the limit is 120 a minute. Wait a minute and carry on.	Each key or app may send 120 messages a minute; wait a minute.
Too many boards today	This key has made 50 boards in the last 24 hours, and the limit is 50 a day. Carry on with one of them, or wait.	Each key or app may make 50 boards a day through MCP; your plan has its own monthly count too.
A wrong address	This address is 3V3's MCP endpoint: https://mcp.3v3.dev	Use the address exactly, with nothing after it. Opened in a browser it answers 405: it only speaks MCP.