browser_navigate / browser_exec / web_extract refused any URL whose query carried a
credential-NAMED parameter (token, signature, access_token, ...) when the backend was
a cloud provider. That is exactly the shape of magic links, OAuth callbacks and signed
CDN assets, so on Browserbase/Browser Use the agent could not finish a sign-in flow or
open an X video asset ("Blocked: URL contains a credential-like query parameter").
The floor protected nothing: the cloud browser already sees every cookie and typed
password of the session, and with the credential vault it receives the real password at
fill time. Hermes' own secrets leaking into a URL stay blocked by the value-shaped
_PREFIX_RE check (_secret_url_error), which is backend-independent. IMDS and
private-address floors are unchanged.
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