diff --git a/.github/meta/commit.txt b/.github/meta/commit.txt
index 3196ee8bc2..f754bd0d45 100644
--- a/.github/meta/commit.txt
+++ b/.github/meta/commit.txt
@@ -1,3 +1,6 @@
-release: v0.5.2
+fix: add missing `altimate_change` markers for `experimental` block in `opencode.jsonc`
+
+The `experimental` config added in #311 was missing upstream markers,
+causing the Marker Guard CI check to fail on main.
 
 Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
diff --git a/.opencode/opencode.jsonc b/.opencode/opencode.jsonc
index 8f3ffac9cf..e16af2f78a 100644
--- a/.opencode/opencode.jsonc
+++ b/.opencode/opencode.jsonc
@@ -15,7 +15,9 @@
     "github-triage": false,
     "github-pr-search": false,
   },
+  // altimate_change start — disable auto MCP discovery for altimate-code
   "experimental": {
     "auto_mcp_discovery": false,
   },
+  // altimate_change end
 }