diff --git a/schemas/1.1.0/mcp.schema.json b/schemas/1.1.0/mcp.schema.json
index b9367db..4a1e425 100644
--- a/schemas/1.1.0/mcp.schema.json
+++ b/schemas/1.1.0/mcp.schema.json
@@ -64,7 +64,23 @@
         },
         "cwd": {
           "type": "string",
-          "pattern": "^(?:\\./|\\$\\{PLUGIN_ROOT\\}(?:/|$)|\\$\\{PLUGIN_DATA\\}(?:/|$))",
+          "anyOf": [
+            {
+              "pattern": "^\\./"
+            },
+            {
+              "const": "${PLUGIN_ROOT}"
+            },
+            {
+              "pattern": "^\\$\\{PLUGIN_ROOT\\}/"
+            },
+            {
+              "const": "${PLUGIN_DATA}"
+            },
+            {
+              "pattern": "^\\$\\{PLUGIN_DATA\\}/"
+            }
+          ],
           "description": "Plugin-relative, PLUGIN_ROOT-rooted, or PLUGIN_DATA-rooted working directory. Filesystem containment is validated separately."
         }
       },