diff --git a/Gemfile b/Gemfile
index 1befb34..f0ea5c2 100644
--- a/Gemfile
+++ b/Gemfile
@@ -41,7 +41,7 @@ gem "toolchest", "~> 0.3.7"
 # unbounded stdio line buffer, unbounded session retention). toolchest 0.3.x
 # still targets the 0.11 signatures, so config/initializers/toolchest_mcp_compat.rb
 # bridges the two — read it before bumping either gem.
-gem "mcp", "~> 1.4.0"
+gem "mcp", "~> 1.5.0"
 gem "jb" # JSON view layer for toolbox actions
 
 # Audit logging
diff --git a/Gemfile.lock b/Gemfile.lock
index 4416605..20d0f0a 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -291,7 +291,7 @@ GEM
       net-smtp
     marcel (1.2.1)
     matrix (0.4.3)
-    mcp (1.4.0)
+    mcp (1.5.0)
       json_schemer (>= 2.4)
     mini_magick (5.3.3)
       logger
@@ -725,7 +725,7 @@ GEM
       addressable (~> 2.8)
       faraday (>= 0.17.5, < 3.a)
       jwt (>= 1.5, < 4.0)
-    simpleidn (0.2.3)
+    simpleidn (0.3.0)
     snaky_hash (2.0.7)
       hashie (>= 0.1.0, < 6)
       version_gem (~> 1.1, >= 1.1.14)
@@ -839,7 +839,7 @@ DEPENDENCIES
   jb
   kramdown
   letter_opener_web
-  mcp (~> 1.4.0)
+  mcp (~> 1.5.0)
   mini_magick
   mission_control-jobs
   omniauth