meta: add minimal AGENTS.md

Adds a minimal AGENTS.md and removes the file from various ignore
lists. The initial file merely points to existing documentation and
guidelines.

Signed-off-by: Beth Griggs <bethanyngriggs@gmail.com>

Author: BethGriggs

.gitignore

@@ -163,7 +163,6 @@ install_manifest.txt
 
 # === Rules for AI assistants ===
 CLAUDE.md
-AGENTS.md
 
 # === Global Rules ===
 # Keep last to avoid being excluded

AGENTS.md

@@ -0,0 +1,6 @@
+# Repository instructions
+
+* Follow [CONTRIBUTING.md](CONTRIBUTING.md) when making changes.
+* For security-sensitive changes or reports, follow [SECURITY.md](SECURITY.md).
+* Follow the [AI use policy and guidelines](doc/contributing/ai-guidelines.md)
+  for AI-assisted contributions and communications.

Makefile

@@ -1480,7 +1480,7 @@ else
 LINT_MD_NEWER = -newer tools/.mdlintstamp
 endif
 
-LINT_MD_TARGETS = doc src lib benchmark test tools/doc tools/icu $(filter-out CLAUDE.md AGENTS.md,$(wildcard *.md))
+LINT_MD_TARGETS = doc src lib benchmark test tools/doc tools/icu $(filter-out CLAUDE.md,$(wildcard *.md))
 LINT_MD_FILES = $(shell $(FIND) $(LINT_MD_TARGETS) -type f \
 	! -path '*node_modules*' ! -path 'test/fixtures/*' -name '*.md' \
 	$(LINT_MD_NEWER))

eslint.config.mjs

@@ -398,7 +398,7 @@ export default [
   // #region markdown config
   {
     files: ['**/*.md'],
-    ignores: ['CLAUDE.md', 'AGENTS.md'],
+    ignores: ['CLAUDE.md'],
     plugins: {
       markdown,
     },