diff --git a/DESIGN.md b/DESIGN.md
index e6ceb2f..0fe3eb7 100644
--- a/DESIGN.md
+++ b/DESIGN.md
@@ -31,7 +31,7 @@ Browser -> /api/chat ->  FastAPI ->  agent.run_turn -> Claude
 
 ## Hallucination and safety controls
 
-A system prompt is _mostly_ reliable, but models will forget or ignore them from time to time. I've added guardrails on tools (similar to hooks you'd see in Claude Code) to further enforce safety controls. There's also an output validation layer that uses good old-fasioned regex to prevent unapproved responses from being sent to the user.
+A system prompt is _mostly_ reliable, but models will forget or ignore them from time to time. I've added guardrails on tools (similar to hooks you'd see in Claude Code) to further enforce safety controls. There's also an output validation layer that uses good old-fashioned regex to prevent unapproved responses from being sent to the user.
 
 | Layer | Catches | Cost |
 |---|---|---|