Put Your Own Logic Inside the Codex Agentic Loop

Codex hooks provide a mechanism to inject custom logic into an agent's execution lifecycle at specific event points like `SessionStart` or `Stop`. These hooks consist of an event, a matcher, and a handler, allowing developers to run scripts that can inspect, validate, or modify the agent's behavior. A case study demonstrates using a `Stop` hook to create a quality gate for a research agent, which validates a generated brief against criteria like source count and diversity. If the validation fails, the hook provides feedback, prompting the agent to continue refining its work until the requirements are met, thereby adding deterministic logic to the agentic loop.