diff --git a/agent/model_metadata.py b/agent/model_metadata.py
index 4df8a6077791..db6885ecf1fa 100644
--- a/agent/model_metadata.py
+++ b/agent/model_metadata.py
@@ -210,8 +210,8 @@ def _strip_provider_prefix(model: str) -> str:
     "grok": 131072,             # catch-all (grok-beta, unknown grok-*)
     # Kimi
     "kimi": 262144,
-    # Tencent — Hy3 Preview (Hunyuan) with 256K context window
-    "hy3-preview": 256000,
+    # Tencent — Hy3 Preview (Hunyuan) with 256K context window (262144 tokens)
+    "hy3-preview": 262144,
     # Nemotron — NVIDIA's open-weights series (128K context across all sizes)
     "nemotron": 131072,
     # Arcee
diff --git a/tests/hermes_cli/test_tencent_tokenhub_provider.py b/tests/hermes_cli/test_tencent_tokenhub_provider.py
index 62cecaeb0c31..d1035dcfa27d 100644
--- a/tests/hermes_cli/test_tencent_tokenhub_provider.py
+++ b/tests/hermes_cli/test_tencent_tokenhub_provider.py
@@ -309,7 +309,7 @@ class TestTencentTokenhubContextLength:
     def test_hy3_preview_context_length(self):
         from agent.model_metadata import get_model_context_length
         ctx = get_model_context_length("hy3-preview")
-        assert ctx == 256000
+        assert ctx == 262144
 
 
 # =============================================================================