diff --git a/internal/agent/tools/grep.md b/internal/agent/tools/grep.md
index 2fe104ba4a7cf006d21c7b531f5ff9af85874979..6cebf1834e8f913f8ae76928712b08bdf577fe8c 100644
--- a/internal/agent/tools/grep.md
+++ b/internal/agent/tools/grep.md
@@ -1,4 +1,4 @@
-Fast content search tool that finds files containing specific text/patterns, returning matching paths sorted by modification time (newest first).
+Search file contents by regex or literal text; returns matching file paths sorted by modification time (max 100); respects .gitignore. Use glob to filter by filename, not contents.
 
 <usage>
 - Provide regex pattern to search within file contents