The file was loaded. The rules just weren't followed. Here's the two-failure diagnostic that tells you which one you have — and what to do for each.
My agent used to follow my rules. The output-format rules, written once into a CLAUDE.md, were obeyed like law — for months, in Claude Code.
Then I migrated to OpenCode, and the rules quietly stopped meaning anything. The agent quoted them back flawlessly. It recited them every time I asked. And it ignored them, day after day, rule after rule. The file was loaded. The rules just weren't obeyed.
The fix wasn't stronger wording, and it wasn't a better prompt. It was re-declaring every rule, one by one, into a fresh AGENTS.md — and it held.
That's the lesson this post is built on: a rule that isn't followed is one of two failures. Either it never loaded, or it loaded and lost. Here's how to tell which, and what to do for each.
