diff --git a/.github/scripts/run_integration_tests.py b/.github/scripts/run_integration_tests.py
index 90627d1386..2e5513eb87 100644
--- a/.github/scripts/run_integration_tests.py
+++ b/.github/scripts/run_integration_tests.py
@@ -486,7 +486,8 @@ def main() -> None:
     print(f"[integration] wheel={wheel.name} sdist={sdist.name} profile={args.profile}")
 
     if args.profile == "mcp-v1":
-        for mcp_version in ("1.19.0", "1.29.0"):
+        # MCP 1.21.2 includes the Pydantic 2.14 import fix and the OAuth 401 scope hotfix.
+        for mcp_version in ("1.21.2", "1.29.0"):
             environment_kind = f"mcp-v1-{mcp_version}"
             python = create_environment(
                 environment_kind,
diff --git a/pyproject.toml b/pyproject.toml
index 2fda55bf0d..cabbce26bc 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -13,7 +13,7 @@ dependencies = [
     "typing-extensions>=4.12.2, <5",
     "requests>=2.0, <3",
     "websockets>=15.0, <17",
-    "mcp>=1.19.0, <3; python_version >= '3.10'",
+    "mcp>=1.21.2, <3; python_version >= '3.10'",
     # Security floors for transitive runtime dependencies.
     "httpx2>=2.12.0",
     "pyjwt>=2.15.0",
diff --git a/uv.lock b/uv.lock
index 412e6374dc..90d4ea4dc0 100644
--- a/uv.lock
+++ b/uv.lock
@@ -2905,7 +2905,7 @@ requires-dist = [
     { name = "h2", marker = "extra == 'modal'", specifier = ">=4.4.1" },
     { name = "httpx2", specifier = ">=2.12.0" },
     { name = "litellm", marker = "extra == 'litellm'", specifier = ">=1.83.0" },
-    { name = "mcp", marker = "python_full_version >= '3.10'", specifier = ">=1.19.0,<3" },
+    { name = "mcp", marker = "python_full_version >= '3.10'", specifier = ">=1.21.2,<3" },
     { name = "modal", marker = "extra == 'modal'", specifier = "==1.4.3" },
     { name = "numpy", marker = "python_full_version >= '3.10' and extra == 'voice'", specifier = ">=2.2.0,<3" },
     { name = "openai", specifier = ">=3.0.0,<4" },