A claim link is the one-time URL ToolRouter gives your agent so you can turn the anonymous account it created on first connect into an account you own — which is what unlocks paid tools and keeps your history across sessions.
When an agent connects to ToolRouter without an API key, the gateway provisions an account silently so free tools work immediately. That account belongs to the session, not to a person. The claim link is how a person takes ownership of it.
Why it matters
It is the reason there is no sign-up wall. You can connect an agent and run a free tool before you have created anything. Nothing is asked for until something is actually needed.
The link arrives with the first tool result, addressed to the agent as a note to pass on: the account is anonymous and belongs to this session, free tools work exactly as they are with no sign-up, and signing in is only needed to pay for paid tools or to keep the account and its history. It is instant if you are already signed in on toolrouter.com, about 30 seconds otherwise. The same URL is also returned by account_setup, and attached to the error when a paid call is attempted on an unclaimed account.
Until it is claimed, an account cannot buy credits, run paid tools, save provider credentials, or create additional API keys, and its history is not recoverable if the session ends.