AWS DevOps Agent is GA and included with Support plans. But it doesn't replace your custom agents -- it complements them. Here's the hybrid pattern: what to buy, what to build, and how MCP bridges the gap.
I woke up to 204 pull requests from a single autonomous agent running overnight. 12 hours, ~$900 in Bedrock tokens, 509 failed builds, zero features shipped. Prompt-only safeguards all failed. Here's the 3-layer fix — hard kill switch, atomic circuit breakers, drift observability — that now prevents runaway agents.