From 938b8ab746ee699cdcf1f329de501c8a7e781531 Mon Sep 17 00:00:00 2001
From: Avi Fenesh <55848801+avifenesh@users.noreply.github.com>
Date: Wed, 25 Feb 2026 12:41:24 +0200
Subject: [PATCH] languages: Add `.mdc` as a recognized Markdown file suffix
 (#50074)

Highlight files ending in `.mdc` as Markdown.

The `.mdc` extension is used by Cursor for its Markdown-based rule files
(`.cursor/rules/*.mdc`). These files are standard Markdown with optional
YAML frontmatter, which the existing Markdown grammar already handles
well. Adding `.mdc` to the recognized suffixes ensures proper syntax
highlighting out of the box.

This was requested during review of the agnix extension PR
([zed-industries/extensions#4743](https://github.com/zed-industries/extensions/pull/4743))
by @MrSubidubi as the preferred approach over defining a custom MDC
language in an extension.

Release Notes:

- Added `.mdc` as a recognized Markdown file extension.
---
 crates/languages/src/markdown/config.toml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crates/languages/src/markdown/config.toml b/crates/languages/src/markdown/config.toml
index 10b1e49757edc106c76e0dc7c591098ebdc6723f..5e7acd230b6f191aebff609bbc1087fbff8d3909 100644
--- a/crates/languages/src/markdown/config.toml
+++ b/crates/languages/src/markdown/config.toml
@@ -1,6 +1,6 @@
 name = "Markdown"
 grammar = "markdown"
-path_suffixes = ["md", "mdx", "mdwn", "markdown", "MD"]
+path_suffixes = ["md", "mdx", "mdwn", "mdc", "markdown", "MD"]
 completion_query_characters = ["-"]
 block_comment = { start = "<!--", prefix = "", end = "-->", tab_size = 0 }
 autoclose_before = ";:.,=}])>"