Claim your ~handle
This page runs its claim in the browser. Here are the two ways in that do not need one.
From a terminal
npm install -g @truealter/cli
alter register
alter register claims a ~handle and creates the account in the same call. If you already have one, run alter login instead.
Over MCP
Add a custom connector named Alter pointed at https://mcp.truealter.com/api/v1/mcp. The anonymous tools answer with no account at all, and signing in through the browser opens the rest.
A ~handle is free and yours once taken. The getting-started guide walks the whole path, and the record says what ~Alter is.