diff --git a/src/mcp/requirements-mcp.txt b/src/mcp/requirements-mcp.txt
index 29285e9..b4d9907 100644
--- a/src/mcp/requirements-mcp.txt
+++ b/src/mcp/requirements-mcp.txt
@@ -2,7 +2,7 @@
 # Pinned to the versions validated in the sandbox venv (2026-08-05).
 # Update deliberately via: pip install -U <pkg> && pip freeze | grep -iE '^(mcp|fastmcp|pyyaml|sqlite-vec|fastembed)'
 mcp==1.29.0
-fastmcp==3.4.6
+fastmcp==4.0.3
 pyyaml==6.0.3
 sqlite-vec==0.1.9
 fastembed==0.8.0
diff --git a/src/mcp/requirements-vision.txt b/src/mcp/requirements-vision.txt
index db07f3d..08b44ea 100644
--- a/src/mcp/requirements-vision.txt
+++ b/src/mcp/requirements-vision.txt
@@ -1,3 +1,3 @@
 mcp==1.29.0
-fastmcp==3.4.6
+fastmcp==4.0.3
 httpx==0.28.1