diff --git a/pyproject.toml b/pyproject.toml
index a87bed2..a0c665a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -65,7 +65,7 @@ Repository = "https://github.com/SpecLeft/specleft"
 
 [project.optional-dependencies]
 mcp = [
-    "fastmcp<3",
+    "fastmcp<4",
 ]
 dev = [
     "pytest-cov",
diff --git a/requirements-dev.txt b/requirements-dev.txt
index 8b44792..e9c861a 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -3,7 +3,7 @@ pytest-cov==4.0.0
 pytest-subtests==0.15.0
 pytest-asyncio==0.25.3
 tiktoken==0.12.0
-fastmcp<3
+fastmcp<4
 build
 black==26.1.0
 ruff==0.5.6