diff --git a/app/mcp.py b/app/mcp.py
index 8c88ab6..02ad15d 100644
--- a/app/mcp.py
+++ b/app/mcp.py
@@ -1,3 +1,12 @@
 from mcp.server.fastmcp import FastMCP
 
-mcp = FastMCP("redmine")
+mcp = FastMCP(
+    "redmine",
+    instructions=(
+        "You are connected to a Redmine project management server. "
+        "Redmine renders text fields (descriptions, comments, wiki pages) as Markdown. "
+        "Always use Markdown syntax for formatting — headings (#), bold (**text**), "
+        "italic (*text*), code (`code`), code blocks (```), lists (- item), "
+        "and links ([text](url)). Never use HTML tags."
+    ),
+)