diff --git a/internal/agent/tools/download.md b/internal/agent/tools/download.md
index 38224e5f6cde90832574cbc629153a4293f2878a..5bfb4d1c66cd83e04a5f98930deb41ed90b6a876 100644
--- a/internal/agent/tools/download.md
+++ b/internal/agent/tools/download.md
@@ -1,4 +1,4 @@
-Downloads binary data from URL and saves to local file.
+Download a URL directly to a local file (binary-safe, streaming, max 100MB); overwrites without warning. For reading content into context use fetch.
 
 <usage>
 - Provide URL to download from