More and more SMBs work with AI assistants like Claude: answering emails, maintaining website content, preparing invoices. For this to work, the AI needs access to your tools. And this is exactly where something dangerous often happens in practice: API keys and passwords end up in a Google Drive document, in a note, or get copied straight into the chat.
The problem: credentials lying around everywhere
What Claude can read, Claude can also repeat. If an API key sits in a document the AI accesses via a connector, it becomes part of every conversation in which that document comes up. Add to that shared folders, syncing across several devices and chat histories that stay saved. A single key quickly ends up in five places – and none of them is made to protect secrets.
The basic principle: use without seeing
The most important rule is simple: Claude should be able to use credentials without ever seeing them. Keys are only retrieved at the moment of use and never end up in prompts, documents or the AI’s memory.
The cloud solution: Cloudflare Workers
Our preferred setup runs entirely in the cloud:
- The credentials are stored as encrypted secrets in a Cloudflare Worker.
- Claude only calls the Worker – not the actual tool.
- The Worker inserts the key and talks to the API. Claude only sees the result.
The big advantage: this works in Claude Chat, in Cowork and in automated routines – even on the go on an iPad or smartphone. No laptop needed, no credentials on any device.
The fallback: a password vault on your computer
Not every tool can be connected via a Worker. For these cases, a local password vault is a good fit:
- 1Password with its command-line tool and a service account: Claude Code or Cowork fetches the key at runtime, without access to the whole vault.
- Apple Keychain on the Mac: credentials sit securely in your iCloud account and are only retrieved when needed.
Important: never let Claude output the value. As soon as a key is shown in the chat, it’s part of the history again.
Dos and don’ts
- Immediately renew any key that has ever appeared in a chat.
- One separate key per tool, with only the permissions it really needs.
- Search connected storage for files containing «password» or «API key» and clean them up.
- No credentials in notes, text files or spreadsheets.
Conclusion
Using AI productively and protecting credentials properly aren’t mutually exclusive – it just takes the right setup, once. If that’s too technical for you: Marketing March is happy to set up this environment for your business, so you can use AI safely, on the go too.
