diff --git a/oh-my-openagent.claude.jsonc b/oh-my-openagent.claude.jsonc
index 5b214a7..b6816b0 100644
--- a/oh-my-openagent.claude.jsonc
+++ b/oh-my-openagent.claude.jsonc
@@ -2,7 +2,7 @@
   "$schema": "https://raw.githubusercontent.com/code-yeongyu/oh-my-openagent/dev/assets/oh-my-opencode.schema.json",
   "agents": {
     "sisyphus": { "model": "anthropic/claude-opus-4-7", "variant": "max" },
-    "hephaestus": { "model": "openai/gpt-5.5", "variant": "medium" },
+    "hephaestus": { "model": "openai/gpt-5.5", "variant": "high" },
     "oracle": { "model": "openai/gpt-5.5", "variant": "high" },
     "librarian": { "model": "openai/gpt-5.4-mini" },
     "explore": { "model": "openai/gpt-5.4-mini" },