diff --git a/server/src/tools/formatter.py b/server/src/tools/formatter.py
index e69de29..58edfac 100644
--- a/server/src/tools/formatter.py
+++ b/server/src/tools/formatter.py
@@ -0,0 +1,31 @@
+from tclint.format import Formatter as BaseFormatter
+from typing import List
+
+
+class NxFormatter(BaseFormatter):
+    """
+    Custom formatter that inherits from tclint's Formatter but preserves explicit
+    line continuations (\\) inside braced expressions when they span multiple lines.
+
+    This avoids generating syntax errors in environments that require a trailing
+    backslash for multi-line expressions (e.g., certain NX Post interpreters),
+    while leaving all other formatting behavior unchanged.
+    """
+
+    def format_braced_expression(self, expr) -> List[str]:  # type: ignore[override]
+        # This method mirrors BaseFormatter.format_braced_expression but inserts
+        # a line continuation (" \") between continuation lines similar to
+        # BaseFormatter.format_expression.
+        formatted = [""]
+        for child in expr.children:
+            lines = self.format(child)
+            formatted[-1] += lines[0]
+            for line in lines[1:]:
+                # add continuation on the previous line; keep next line at the same level
+                formatted[-1] += " \\"  # keep explicit continuation
+                formatted += [line]
+
+        if expr.pos[0] == expr.end_pos[0]:
+            return self._brace(formatted)
+
+        return ["{"] + self._indent(formatted, self.opts.indent) + ["}"]