diff --git a/README.md b/README.md
index e85c8ac..406db50 100644
--- a/README.md
+++ b/README.md
@@ -23,7 +23,7 @@ Pass an absolute file path to any tool and the format is auto-detected.
 
 - Python 3.10+
 - Dependencies listed in `requirements.txt`:
-  - `mcp[cli]` — Model Context Protocol SDK
+  - `mcp[cli]>=1.28,<2` — Model Context Protocol SDK (v1.x; v2 removed `mcp.server.fastmcp`)
   - `lief>=0.17.0` — binary parsing library
 
 ## Installation
diff --git a/requirements.txt b/requirements.txt
index b8ea38d..d0dbde8 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,2 +1,2 @@
-mcp[cli]
+mcp[cli]>=1.28,<2
 lief>=0.17.0