From cdf4d750ef0b87f96686ec6f599654809b879518 Mon Sep 17 00:00:00 2001
From: Jonathan Hefner <jonathan@hefner.pro>
Date: Mon, 31 Aug 2026 16:54:21 -0700
Subject: [PATCH] Make MCP working-directory validation regex-portable
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Replace the 1.1.0 `cwd` regular expression with direct `anyOf`
alternatives for the forms defined by §7.2.1. Use `const` for exact
`${PLUGIN_ROOT}` and `${PLUGIN_DATA}` values and simple prefix patterns
for rooted paths so validators do not depend on noncapturing groups or
engine-specific `$` behavior.
---
 schemas/1.1.0/mcp.schema.json | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

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."
         }
       },