From 47d55362a4318ed381aa557616d0e411cb5016cf Mon Sep 17 00:00:00 2001
From: Ari Webb <arijwebb@gmail.com>
Date: Mon, 23 Feb 2026 18:08:47 -0800
Subject: [PATCH] fix: models need to be paginated (#9621)

---
 letta/schemas/providers/anthropic.py    | 10 ++--
 tests/managers/test_provider_manager.py | 67 ++++++++++++++++++-------
 2 files changed, 53 insertions(+), 24 deletions(-)

diff --git a/letta/schemas/providers/anthropic.py b/letta/schemas/providers/anthropic.py
index 398c3cfe..554519b3 100644
--- a/letta/schemas/providers/anthropic.py
+++ b/letta/schemas/providers/anthropic.py
@@ -182,7 +182,11 @@ class AnthropicProvider(Provider):
             raise ValueError("No API key provided")
 
         try:
-            models = await anthropic_client.models.list()
+            # Auto-paginate through all pages to ensure we get every model.
+            # The default page size is 20, and Anthropic now has more models than that.
+            models_data = []
+            async for model in anthropic_client.models.list():
+                models_data.append(model.model_dump())
         except AttributeError as e:
             if "_set_private_attributes" in str(e):
                 raise LLMError(
@@ -191,10 +195,6 @@ class AnthropicProvider(Provider):
                 )
             raise
 
-        models_json = models.model_dump()
-        assert "data" in models_json, f"Anthropic model query response missing 'data' field: {models_json}"
-        models_data = models_json["data"]
-
         return self._list_llm_models(models_data)
 
     def _list_llm_models(self, models) -> list[LLMConfig]:
diff --git a/tests/managers/test_provider_manager.py b/tests/managers/test_provider_manager.py
index 183417cc..94b9593c 100644
--- a/tests/managers/test_provider_manager.py
+++ b/tests/managers/test_provider_manager.py
@@ -557,16 +557,31 @@ async def test_server_startup_syncs_base_providers(default_user, default_organiz
     async def mock_openai_get_model_list_async(*args, **kwargs):
         return mock_openai_models
 
-    # Mock Anthropic models.list() response
-    from unittest.mock import MagicMock
+    # Mock Anthropic models.list() response as an async iterable
+    # (the real SDK returns an AsyncPage that supports async iteration)
 
-    mock_anthropic_response = MagicMock()
-    mock_anthropic_response.model_dump.return_value = mock_anthropic_models
+    class MockAnthropicModelItem:
+        def __init__(self, data):
+            self._data = data
+
+        def model_dump(self):
+            return self._data
+
+    class MockAnthropicAsyncPage:
+        def __init__(self, items):
+            self._items = [MockAnthropicModelItem(item) for item in items]
+
+        def __aiter__(self):
+            return self._async_iter()
+
+        async def _async_iter(self):
+            for item in self._items:
+                yield item
 
     # Mock the Anthropic AsyncAnthropic client
     class MockAnthropicModels:
         async def list(self):
-            return mock_anthropic_response
+            return MockAnthropicAsyncPage(mock_anthropic_models["data"])
 
     class MockAsyncAnthropic:
         def __init__(self, *args, **kwargs):
@@ -833,24 +848,38 @@ async def test_server_startup_handles_api_errors_gracefully(default_user, defaul
     async def mock_openai_fail(*args, **kwargs):
         raise Exception("OpenAI API is down")
 
-    # Mock Anthropic to succeed
-    from unittest.mock import MagicMock
+    # Mock Anthropic to succeed (as async iterable, matching real SDK pagination)
 
-    mock_anthropic_response = MagicMock()
-    mock_anthropic_response.model_dump.return_value = {
-        "data": [
-            {
-                "id": "claude-3-5-sonnet-20241022",
-                "type": "model",
-                "display_name": "Claude 3.5 Sonnet",
-                "created_at": "2024-10-22T00:00:00Z",
-            }
-        ]
-    }
+    mock_anthropic_data = [
+        {
+            "id": "claude-3-5-sonnet-20241022",
+            "type": "model",
+            "display_name": "Claude 3.5 Sonnet",
+            "created_at": "2024-10-22T00:00:00Z",
+        }
+    ]
+
+    class MockAnthropicModelItem:
+        def __init__(self, data):
+            self._data = data
+
+        def model_dump(self):
+            return self._data
+
+    class MockAnthropicAsyncPage:
+        def __init__(self, items):
+            self._items = [MockAnthropicModelItem(item) for item in items]
+
+        def __aiter__(self):
+            return self._async_iter()
+
+        async def _async_iter(self):
+            for item in self._items:
+                yield item
 
     class MockAnthropicModels:
         async def list(self):
-            return mock_anthropic_response
+            return MockAnthropicAsyncPage(mock_anthropic_data)
 
     class MockAsyncAnthropic:
         def __init__(self, *args, **kwargs):