diff --git a/.gitignore b/.gitignore
index 49c54dc6..09ae1ea4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -28,3 +28,6 @@ proptest-regressions/
 .claude/worktrees/
 *~
 /roadmap.html
+
+# prolog-mcp session files (server writes ./prolog-sessions relative to cwd)
+prolog-sessions/