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+# CLAUDE.md
+
+This file provides guidance to Claude Code (and other AI agents) working
+in this repository.
+
+See [`../ai/CLAUDE.md`](../ai/CLAUDE.md) (or
+https://github.com/Postgres-Extensions/ai/blob/main/CLAUDE.md if that path
+doesn't exist locally — clone it to `../ai/` per its own first instruction),
+`../ai/PR.md`, and `../ai/CODE_STYLE.md` for cross-repo conventions (CI
+monitoring, PR/commit conventions, executable-bit safety, comment style,
+etc.) that apply here too.
+
+## About this repo
+
+`linter` is the style linter shared across Postgres-Extensions projects
+(see README.md) — currently just the `sql/` SQL style linter. Consumer
+repos vendor it as a git submodule (`.vendor/linter`) plus a thin
+tracked `lint.mk`, not via pgxntool — this repo has no `pgxntool/` build
+system to defer to, unlike most others in this org.