D213 — Every AGENTS.md gets a one-line CLAUDE.md import beside it

Decision. Every directory that holds an AGENTS.md also holds a CLAUDE.md containing exactly @AGENTS.md. That includes the two area files, internal/mcpserver/ and internal/provisioning/, not only the root. No directory holds an AGENTS.override.md. internal/repodocs enforces both rules on every instruction directory, where it used to check the root file only.

Why. Claude Code does not read the name AGENTS.md at any depth. It discovers a nested CLAUDE.md and injects it the first time it reads a file in that directory. So until now the area rules reached Claude only if the agent followed the root file's instruction to "read it before editing there". For internal/provisioning, a missed rule does not fail a test: the package writes into other people's home directories. Codex, Kiro and Antigravity already read the nested AGENTS.md themselves, so the import adds nothing for them. It costs 11 bytes per area.

AGENTS.override.md is banned because Codex reads it instead of the AGENTS.md in the same directory, not in addition to it. One override would silently hide that directory's rules from Codex only. The chain budget already counted override files; nothing prevented one from being added.

Alternatives rejected. - Rely on the root pointer. Claude only gets the rules if it remembers the instruction, which is exactly what automatic loading exists to avoid. - A symlink instead of the import. D207's reason still holds: a Windows checkout without Developer Mode turns it into a text file, and the rules would silently fail to load. - .claude/rules/*.md with paths: globs. It is more precise, but it is a second place for the same rules, and no repository measured uses it yet.

Consequences. Adding an area AGENTS.md means adding its CLAUDE.md in the same change. make test names the missing one. A Codex override now fails the build rather than shadowing the rules.