Anthropic Engineering
Anthropic: users approved 93% of permission prompts, so containment beats supervision
Human-in-the-loop approval fatigue is real and measurable. Telemetry showed users approving roughly 93% of Claude Code permission prompts, and in a February 2026 internal red team, a phished employee's pasted prompt got Claude to read ~/.aws/credentials and POST them out in 24 of 25 attempts, with nothing anomalous for a classifier to catch because the instruction came from the user. The fixes are environmental: an OS-level sandbox that cut permission prompts 84%, a VM for Claude Cowork that keeps credentials in the host keychain, and a man-in-the-middle proxy after a disclosure showed an allowlisted api.anthropic.com could be used to upload a victim's files to an attacker's Anthropic account. The recurring lesson is that gVisor, seccomp, and the hypervisors held, while the custom proxy Anthropic built itself is what broke.
- #agents
- #security
