diff --git a/pyproject.toml b/pyproject.toml
index fe0686f..5cf1da7 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,7 +1,7 @@
 [project]
 authors = [{ name = "Aman Rusia", email = "gapypi@arcfu.com" }]
 name = "wcgw"
-version = "1.0.2"
+version = "1.0.3"
 description = "What could go wrong giving full shell access to chatgpt?"
 readme = "README.md"
 requires-python = ">=3.10, <3.13"
diff --git a/src/wcgw/types_.py b/src/wcgw/types_.py
index b05e38b..aa24e77 100644
--- a/src/wcgw/types_.py
+++ b/src/wcgw/types_.py
@@ -16,6 +16,22 @@ class BashInteraction(BaseModel):
     send_specials: Optional[Sequence[Specials]] = None
     send_ascii: Optional[Sequence[int]] = None
 
+    def model_post_init(self, __context: object) -> None:
+        # Ensure only one of the fields is set
+        if (
+            sum(
+                [
+                    int(bool(self.send_text)),
+                    int(bool(self.send_specials)),
+                    int(bool(self.send_ascii)),
+                ]
+            )
+            != 1
+        ):
+            raise ValueError(
+                "Exactly one of 'send_text', 'send_specials', or 'send_ascii' must be set"
+            )
+
 
 class ReadImage(BaseModel):
     file_path: str