From 8ce9ff6a221a04299de5912a8b22c9d6270a565e Mon Sep 17 00:00:00 2001
From: Yufeng He <40085740+he-yufeng@users.noreply.github.com>
Date: Tue, 12 May 2026 16:19:03 +0800
Subject: [PATCH] fix: consume anthropic beta flags

---
 .../agent_framework_anthropic/_chat_client.py  |  1 +
 .../anthropic/tests/test_anthropic_client.py   | 18 ++++++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/python/packages/anthropic/agent_framework_anthropic/_chat_client.py b/python/packages/anthropic/agent_framework_anthropic/_chat_client.py
index 98c181f152..b4982deeaa 100644
--- a/python/packages/anthropic/agent_framework_anthropic/_chat_client.py
+++ b/python/packages/anthropic/agent_framework_anthropic/_chat_client.py
@@ -617,6 +617,7 @@ def _prepare_options(
 
         # betas
         run_options["betas"] = self._prepare_betas(options)
+        run_options.pop("additional_beta_flags", None)
 
         # extra headers
         run_options["extra_headers"] = {"User-Agent": get_user_agent()}
diff --git a/python/packages/anthropic/tests/test_anthropic_client.py b/python/packages/anthropic/tests/test_anthropic_client.py
index 0cfec3423c..3c5b830a59 100644
--- a/python/packages/anthropic/tests/test_anthropic_client.py
+++ b/python/packages/anthropic/tests/test_anthropic_client.py
@@ -946,6 +946,24 @@ async def test_prepare_options_with_tool_choice_auto(
     assert "allow_multiple_tool_calls" not in run_options
 
 
+async def test_prepare_options_consumes_additional_beta_flags(
+    mock_anthropic_client: MagicMock,
+) -> None:
+    client = create_test_anthropic_client(mock_anthropic_client)
+
+    messages = [Message(role="user", contents=["Hello"])]
+    run_options = client._prepare_options(
+        messages,
+        {
+            "model": "claude-3-5-sonnet-20241022",
+            "additional_beta_flags": ["extended-cache-ttl-2025-04-11"],
+        },
+    )
+
+    assert "extended-cache-ttl-2025-04-11" in run_options["betas"]
+    assert "additional_beta_flags" not in run_options
+
+
 async def test_prepare_options_with_tool_choice_required(
     mock_anthropic_client: MagicMock,
 ) -> None: