diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 98c045960..8814146c9 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -215,3 +215,9 @@ jobs:
           --ignore=tests/unit/test_transcript_action_workflow.py -k "not integration"
       - name: Offline MCP inventory and approval regressions
         run: python -m pytest tests/security/test_local_mcp_config.py tests/security/test_mcp_catalog_approval.py -q -o addopts=''
+      - name: Anthropic SDK 2 client compatibility
+        run: >-
+          PYTHONPATH=src uv run --no-project --python "${{ matrix.python-version }}"
+          --with pytest --with anthropic==2.0.0 --with httpx2
+          --with aiohttp --with pydantic
+          python -m pytest tests/compat/test_anthropic_v2_compat.py -q -o addopts=''
diff --git a/pyproject.toml b/pyproject.toml
index 325701cea..116d1e566 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -144,7 +144,7 @@ ml = [
     "tokenizers>=0.15.0",
     "sentence-transformers>=2.2.0",
     "openai>=1.3.0",
-    "anthropic>=0.105.0,<2",
+    "anthropic>=0.105.0,<3",
     "google-generativeai>=0.3.0",
     "cohere>=4.37.0",
     "numpy>=1.24.0",
diff --git a/tests/compat/test_anthropic_v2_compat.py b/tests/compat/test_anthropic_v2_compat.py
new file mode 100644
index 000000000..b044d24af
--- /dev/null
+++ b/tests/compat/test_anthropic_v2_compat.py
@@ -0,0 +1,81 @@
+import asyncio
+import json
+
+import pytest
+
+anthropic = pytest.importorskip("anthropic", minversion="2.0")
+httpx = pytest.importorskip("httpx2")
+
+from agents.mcp_tools.tri_model_consensus_tool import TriModelConsensusTool
+from unified_ai_sdk import AIRequest, ModelProvider, TaskType, UnifiedAISDK
+from youtube_extension.core.mcp.context_manager import MCPContext
+from youtube_extension.core.mcp.protocol_bridge import AnthropicAdapter
+
+calls = []
+
+
+def respond(request: httpx.Request) -> httpx.Response:
+    payload = json.loads(request.content)
+    calls.append((request.url.path, request.headers.get("anthropic-version"), payload))
+    if request.url.path.endswith("/count_tokens"):
+        return httpx.Response(200, json={"input_tokens": 1})
+    return httpx.Response(
+        200,
+        json={
+            "id": "msg_test",
+            "type": "message",
+            "role": "assistant",
+            "content": [{"type": "text", "text": "mocked response"}],
+            "model": "claude-opus-4-8",
+            "stop_reason": "end_turn",
+            "stop_sequence": None,
+            "usage": {"input_tokens": 11, "output_tokens": 22},
+        },
+    )
+
+
+async def main():
+    async with httpx.AsyncClient(transport=httpx.MockTransport(respond)) as http_client:
+        client = anthropic.AsyncAnthropic(
+            api_key="sk-ant-test", http_client=http_client
+        )
+        sdk = UnifiedAISDK({"anthropic_api_key": "sk-ant-test", "retry_attempts": 1})
+        sdk._anthropic_client = client
+        result = await sdk.unified_request(
+            AIRequest(
+                prompt="Summarize this",
+                model="claude-opus-4-8",
+                provider=ModelProvider.CLAUDE,
+                task_type=TaskType.SUMMARIZATION,
+            )
+        )
+        assert (
+            result.success
+            and result.content == "mocked response"
+            and result.tokens_used == 33
+        )
+
+        adapter = AnthropicAdapter()
+        assert await adapter.initialize({"api_key": "sk-ant-test"})
+        adapter._client = client
+        context = MCPContext(user="test", task="compat", intent="test Anthropic v2")
+        adapter_result = await adapter.send_request({"prompt": "hello"}, context)
+        assert adapter_result["content"] == "mocked response"
+        assert adapter_result["usage"] == {"input_tokens": 11, "output_tokens": 22}
+        assert await adapter.health_check()
+
+        consensus = object.__new__(TriModelConsensusTool)
+        consensus.claude_client = client
+        consensus_result = await consensus._query_claude("reason", "generic")
+        assert (
+            consensus_result.response == "mocked response"
+            and not consensus_result.error
+        )
+
+    assert len(calls) == 4 and all(version == "2026-10-21" for _, version, _ in calls)
+    assert calls[2][0].endswith("/count_tokens")
+    assert anthropic.__version__.startswith("2.")
+
+
+def test_anthropic_v2_app_callsites():
+    asyncio.run(main())
diff --git a/uv.lock b/uv.lock
index 631beeb5c..9c5f3bbfd 100644
--- a/uv.lock
+++ b/uv.lock
@@ -5671,7 +5671,7 @@ requires-dist = [
     { name = "aiohttp", specifier = ">=3.8.0" },
     { name = "aiosqlite", specifier = ">=0.19.0" },
     { name = "alembic", specifier = ">=1.12.0" },
-    { name = "anthropic", marker = "extra == 'ml'", specifier = ">=0.105.0,<2" },
+    { name = "anthropic", marker = "extra == 'ml'", specifier = ">=0.105.0,<3" },
     { name = "asyncio-throttle", marker = "extra == 'youtube'", specifier = ">=1.0.0" },
     { name = "asyncpg", marker = "extra == 'postgres'", specifier = ">=0.29.0" },
     { name = "black", marker = "extra == 'dev'", specifier = ">=23.0.0" },