Lockbox

Send API keys and private files to a teammate, and to their agent, without pasting them into chat. Ask Claude to share a file or a secret and the Lockbox panel opens in the conversation. Pick the file or type the secret there; it's encrypted in your browser before it leaves. You get one link per person. Links can be locked to the recipient's email, expire, and open a set number of times. Recipients open links in the same panel, in a browser, or with the lockbox command-line tool. Claude never sees your file or secret through Lockbox: a file reaches the conversation only if you click "Send to chat". Lockbox's servers store only encrypted data.