LLM Client Golden Path

Wiring an LLM client is easy to do adequately and easy to get subtly wrong. This is the shape that avoids the traps, plus the failure modes worth knowing before you hit them.

Model ids are deliberately not in this file. They live in references/model-registry.md so there is one place to update when a model is superseded, rather than a grep across every repo.

The shape

1. Read the key from the environment. Never hardcode it, never commit it. Put the variable name in CLAUDE.md, and the value in .env.local (gitignored), a CI secret, or a password manager. If a key is ever committed, rotate it: deleting the file does not remove it from git history.