diff --git a/skills/agent-builder/references/minimal-agent.py b/skills/agent-builder/references/minimal-agent.py
index 5479aed7..a1898cf4 100644
--- a/skills/agent-builder/references/minimal-agent.py
+++ b/skills/agent-builder/references/minimal-agent.py
@@ -18,7 +18,7 @@ import os
 
 # Configuration
 client = Anthropic(api_key=os.getenv("ANTHROPIC_API_KEY"))
-MODEL = os.getenv("MODEL_NAME", "claude-sonnet-4-20250514")
+MODEL = os.getenv("MODEL_NAME", "claude-sonnet-5-5")
 WORKDIR = Path.cwd()
 
 # System prompt - keep it simple
diff --git a/skills/agent-builder/scripts/init_agent.py b/skills/agent-builder/scripts/init_agent.py
index a5c586d9..758e0adb 100644
--- a/skills/agent-builder/scripts/init_agent.py
+++ b/skills/agent-builder/scripts/init_agent.py
@@ -37,7 +37,7 @@ client = Anthropic(
     api_key=os.getenv("ANTHROPIC_API_KEY"),
     base_url=os.getenv("ANTHROPIC_BASE_URL")
 )
-MODEL = os.getenv("MODEL_NAME", "claude-sonnet-4-20250514")
+MODEL = os.getenv("MODEL_NAME", "claude-sonnet-5-5")
 
 SYSTEM = """You are a coding agent. Use bash for everything:
 - Read: cat, grep, find, ls
@@ -97,7 +97,7 @@ client = Anthropic(
     api_key=os.getenv("ANTHROPIC_API_KEY"),
     base_url=os.getenv("ANTHROPIC_BASE_URL")
 )
-MODEL = os.getenv("MODEL_NAME", "claude-sonnet-4-20250514")
+MODEL = os.getenv("MODEL_NAME", "claude-sonnet-5-5")
 WORKDIR = Path.cwd()
 
 SYSTEM = f"""You are a coding agent at {{WORKDIR}}.
@@ -213,7 +213,7 @@ if __name__ == "__main__":
 ENV_TEMPLATE = '''# API Configuration
 ANTHROPIC_API_KEY=sk-xxx
 ANTHROPIC_BASE_URL=https://api.anthropic.com
-MODEL_NAME=claude-sonnet-4-20250514
+MODEL_NAME=claude-sonnet-5-5
 '''