Phase 2: Control & Containment · ~60 minutes · Python (stdlib · three-detector simulator: kill switch · circuit breaker

Kill Switches, Circuit Breakers, and Canary Tokens

A kill switch is a boolean held outside the agent's edit surface — a Redis key, a feature flag, a signed config — that disables the agent entirely.

Hiring signal: Can operate kill switches, circuit breakers, and canary tokens in production

Introduction

A circuit breaker is finer-grained: it trips on a specific pattern (five identical tool calls in a row), pauses the offending path, and escalates to a human. A canary token inherits from classical deception: a fake credential or honeypot record an agent has no legitimate reason to touch, whose access triggers an alert. eBPF-based datapaths (e.g. Cilium) can rewrite a quarantined pod's egress to a forensic honeypot at the kernel layer; published Cilium benchmarks report sub-millisecond P99 datapath latency under load (your propagation budget depends on how a policy update reaches the node, not the datapath itself). Statistical detectors (EWMA, CUSUM) that adapt to a moving baseline will quietly accept drift — layer them with hard constitutional limits that do not bend.

Type: Learn Languages: Python (stdlib, three-detector simulator: kill switch, circuit breaker, canary) Prerequisites: Phase 15 · 13 (Cost governors), Phase 15 · 10 (Permission modes) Time: ~60 minutes

Objective

Learning objectives

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Key terms in this lesson

Agent