diff --git a/common/tools/dev-tool/register.js b/common/tools/dev-tool/register.js
index 30baa8ecbfc6..da82300ff81d 100644
--- a/common/tools/dev-tool/register.js
+++ b/common/tools/dev-tool/register.js
@@ -14,17 +14,20 @@
  */
 
 const path = require("path");
-
-const ts = require("typescript");
-
 const cwd = process.cwd();
 
 // This is the calling module, which will be the node repl context.
-const main = module.parent;
+const main = require.main || module.parent;
 
 // We need to know which package name to monkey patch
 const { name: hostPackageName } = main.require("./package.json");
 
+// We need to use whatever version of TypeScript the calling package uses to inspect syntax nodes, because
+// that is what the ts-node invocation will use, and we need to agree with it on syntax brands.
+const ts = hostPackageName === "@azure/dev-tool"
+    ? require(path.join(cwd, "node_modules", "typescript"))
+    : main.require("typescript");
+
 // If we're bootstrapping a dev-tool command, we need to patch the package from
 // CWD instead.  This will still end up being dev-tool if we end up in a
 // self-hosting situation where dev-tool calls itself from its own scripts.