#hooks

An inspected agent configuration shared by Claude Code and Codex: immutable releases, 4 execution layers, BM25 skill routing and the gaps found. Full report to read online.

Hooks are shell scripts with your user permissions. MCP servers are third-party code with access to your credentials. Their timing and access depend on the configured events and server.

Three configuration layers for project context, daily tools and persistent memory, with checks for what loads and how it behaves.

Separate test creation from implementation, verify the expected failure, and give automated TDD retries an explicit exit path.

Portable instructions require neutral sources, generated runtime outputs, release controls, and behavioral tests. Native primitives alone do not provide portability.

The concepts I wish I’d known before week one: the agent loop, instruction scopes, context management, skill invocation, hooks, and client permission checks.