diff --git a/.github/workflows/mcp-inspector.lock.yml b/.github/workflows/mcp-inspector.lock.yml
index 4eef8f439b3..2c996184978 100644
--- a/.github/workflows/mcp-inspector.lock.yml
+++ b/.github/workflows/mcp-inspector.lock.yml
@@ -1000,7 +1000,7 @@ jobs:
                 "url": "https://mcp.datadoghq.com/api/unstable/mcp-server/mcp?toolsets=core",
                 "headers": {
                   "DD_API_KEY": "\${DD_API_KEY}",
-                  "DD_APPLICATION_KEY": "\${DD_APP_KEY}",
+                  "DD_APPLICATION_KEY": "\${DD_APPLICATION_KEY}",
                   "DD_SITE": "\${DD_SITE}"
                 },
                 "tools": [
diff --git a/.github/workflows/smoke-otel-backends.lock.yml b/.github/workflows/smoke-otel-backends.lock.yml
index 092ac357201..6f51faa9a84 100644
--- a/.github/workflows/smoke-otel-backends.lock.yml
+++ b/.github/workflows/smoke-otel-backends.lock.yml
@@ -773,7 +773,7 @@ jobs:
                 "url": "https://mcp.datadoghq.com/api/unstable/mcp-server/mcp?toolsets=core",
                 "headers": {
                   "DD_API_KEY": "\${DD_API_KEY}",
-                  "DD_APPLICATION_KEY": "\${DD_APP_KEY}",
+                  "DD_APPLICATION_KEY": "\${DD_APPLICATION_KEY}",
                   "DD_SITE": "\${DD_SITE}"
                 },
                 "tools": [
diff --git a/actions/setup/js/mcp_scripts_mcp_server_http.test.cjs b/actions/setup/js/mcp_scripts_mcp_server_http.test.cjs
index c984c134cd0..7e8340fbcf5 100644
--- a/actions/setup/js/mcp_scripts_mcp_server_http.test.cjs
+++ b/actions/setup/js/mcp_scripts_mcp_server_http.test.cjs
@@ -144,7 +144,7 @@ describe("mcp_scripts_mcp_server_http.cjs integration", () => {
     it("should handle missing required arguments", async () => {
       const headers = sessionId ? { "Mcp-Session-Id": sessionId } : {},
         response = await makeRequest({ jsonrpc: "2.0", id: 4, method: "tools/call", params: { name: "echo_tool", arguments: {} } }, headers);
-      (expect(response.status).toBe(200), expect(response.data.error).toBeDefined(), expect(response.data.error.message).toContain("missing"));
+      (expect(response.status).toBe(200), expect(response.data.error).toBeDefined(), expect(response.data.error.message).toContain("not allowed"));
     }),
     afterAll(async () => {
       (serverProcess &&