Write only ASCII characters

Files, commit messages, and issues use only ASCII characters, with <-
and -> for arrows and plain dashes and quotes. Decorative characters
such as a Unicode arrow in a model task text are hard to type and search
for, and they add nothing that ASCII cannot say. Test data that checks
Unicode handling is the only exception.

diff --git a/AGENTS.md b/AGENTS.md
index bfeccf24b3b76c79f2e82f4e4ee0073728810888..7eadd6ddad4f5a7a3b64abc7bf219c19d9751b9c 100644 (file)
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -36,6 +36,9 @@ Read the `SKILL.md` of a skill before you start the task that it covers:
   toolchain, the tools, and every dependency. Keep Nix code in `nix/`.
   Do not install host dependencies or add a dependency that works only
   outside Nix.
+- Write only ASCII characters in files, commit messages, and issues. Use
+  `<-` and `->` for arrows, `-` for dashes, and straight quotes. Use
+  other characters only in test data that checks Unicode handling.
 - Keep secrets and local runtime files out of Git and Nix sources.
 - Do not reveal infrastructure in files, code comments, commit messages,
   or issues. This includes host, server, and domain names, IP addresses,