feat: make Ollama/gemma4 the primary backend with Claude as fallback

Rolls back the claudification backend preference: PREFER_CLOUD_BACKEND now
defaults to false, resolve_backend() picks Ollama first and uses Claude when
explicitly preferred or when the new Ollama startup health check fails. The
Steward retries mid-request failures on the other backend in both directions.

Also hardens the fallback itself: Anthropic SDK imports are lazy so a broken
anthropic package degrades to Ollama-only instead of crashing at import time
(root cause of the production outage since April), anthropic is pinned to a
pydantic-ai-1.27-compatible range, ANTHROPIC_MODEL defaults to claude-sonnet-5
(sonnet-4-20250514 retired 2026-06-15), sampling parameters are stripped from
Claude calls (Sonnet 5 rejects them), and the Steward timeout is configurable
(STEWARD_TIMEOUT, default 60s) since gemma4 needs ~35s warm for analysis.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
This commit is contained in:
2026-07-13 18:35:53 +02:00
co-authored by Claude Fable 5
parent 427ad311dc
commit 033a1c01e8
11 changed files with 323 additions and 71 deletions
+10 -8
View File
@@ -8,17 +8,19 @@ API_HOST=0.0.0.0
API_PORT=8000
API_PREFIX=/v1
# Anthropic Configuration (Claude - preferred backend)
# Set ANTHROPIC_API_KEY to enable Claude as the default backend
# Without an API key, Tatlock uses Ollama exclusively
# ANTHROPIC_API_KEY=sk-ant-api03-your-key-here
ANTHROPIC_MODEL=claude-sonnet-4-20250514
PREFER_CLOUD_BACKEND=true
# Ollama Configuration (local fallback when Claude unavailable)
# Ollama Configuration (local - primary backend)
OLLAMA_HOST=http://localhost:11434
OLLAMA_DEFAULT_MODEL=gemma4:e2b
OLLAMA_TIMEOUT=120
STEWARD_TIMEOUT=60
# Anthropic Configuration (Claude - cloud fallback)
# Set ANTHROPIC_API_KEY to keep the Claude fallback available: it is used
# automatically when Ollama is down, or exclusively when PREFER_CLOUD_BACKEND=true
# Without an API key, Tatlock uses Ollama only
# ANTHROPIC_API_KEY=sk-ant-api03-your-key-here
ANTHROPIC_MODEL=claude-sonnet-5
PREFER_CLOUD_BACKEND=false
# SearXNG Configuration
SEARXNG_HOST=http://localhost:8087
+1
View File
@@ -13,6 +13,7 @@ dependencies = [
"pydantic>=2.11,<2.13",
"pydantic-settings>=2.12,<2.13",
"pydantic-ai-slim[openai,anthropic]>=1.27,<1.28",
"anthropic>=0.77,<1.0",
"httpx>=0.28,<0.29",
"sse-starlette>=3.0,<3.1",
"python-dotenv>=1.2,<1.3",
+6 -6
View File
@@ -204,13 +204,13 @@ async def run_housekeeper(
)
try:
# Use temperature 0.1 for slight exploration
from pydantic_ai.settings import ModelSettings
# Temperature 0.1 for slight exploration (skipped on Claude backend)
from src.anthropic.model_selector import get_sampling_settings
result = await agent.run(
prompt,
message_history=message_history,
model_settings=ModelSettings(temperature=0.1),
model_settings=get_sampling_settings(0.1),
)
logger.info(
@@ -266,13 +266,13 @@ async def run_housekeeper_stream(
)
try:
# Use temperature 0.1 for slight exploration
from pydantic_ai.settings import ModelSettings
# Temperature 0.1 for slight exploration (skipped on Claude backend)
from src.anthropic.model_selector import get_sampling_settings
async with agent.run_stream(
prompt,
message_history=message_history,
model_settings=ModelSettings(temperature=0.1),
model_settings=get_sampling_settings(0.1),
) as response:
async for delta in response.stream_text(delta=True):
yield delta
+24 -10
View File
@@ -11,7 +11,7 @@ Uses plain text output (not JSON) for reliability. Supports both Claude
import httpx
from typing import Optional
from src.anthropic.model_selector import is_claude_available, get_model_info
from src.anthropic.model_selector import get_model_info, is_claude_available, resolve_backend
from src.core.config import config
from src.core.household_registry import get_household_registry
from src.core.logging_config import get_logger
@@ -113,18 +113,19 @@ class StewardAgent:
def __init__(self):
"""Initialize Steward with backend selection based on availability."""
# Ollama config (fallback)
# Ollama config (primary)
self.ollama_host = str(config.OLLAMA_HOST).rstrip('/')
self.ollama_model = config.OLLAMA_DEFAULT_MODEL
# Claude config (preferred)
# Claude config (fallback)
self.claude_model = config.ANTHROPIC_MODEL
self._anthropic_client = None
# Determine which backend to use
self._use_claude = config.PREFER_CLOUD_BACKEND and is_claude_available()
# Determine which backend to use (Ollama-first, Claude when
# preferred via config or when Ollama is down)
self._use_claude = resolve_backend() == "claude"
self.timeout = 30.0 # 30 second timeout for analysis
self.timeout = float(config.STEWARD_TIMEOUT)
model_info = get_model_info()
logger.info(
@@ -145,12 +146,12 @@ class StewardAgent:
"""Call Claude API directly for plain text generation."""
client = self._get_anthropic_client()
# No temperature: rejected by Claude Sonnet 5+ (sampling params deprecated)
response = await client.messages.create(
model=self.claude_model,
max_tokens=1024,
system=system_prompt,
messages=[{"role": "user", "content": user_message}],
temperature=0.3, # Lower = more consistent
)
return response.content[0].text.strip()
@@ -227,20 +228,33 @@ class StewardAgent:
return analysis_text
except Exception as e:
# If Claude fails, try Ollama as fallback
# Mid-request fallback: retry on the other backend when possible
if self._use_claude:
logger.warning(
"steward_claude_fallback",
error=str(e),
)
analysis_text = await self._call_ollama(prompt)
fallback_backend = "ollama_fallback"
elif is_claude_available():
logger.warning(
"steward_ollama_fallback",
error=str(e),
)
analysis_text = await self._call_claude(
system_prompt="You are the Steward of the household, advising the Butler (Tatlock) on which capabilities to use. Be concise and specific.",
user_message=prompt,
)
fallback_backend = "claude_fallback"
else:
raise
logger.debug(
"steward_analysis_received",
backend="ollama_fallback",
backend=fallback_backend,
text_preview=analysis_text[:150],
)
return analysis_text
raise
# Global Steward instance
+8 -1
View File
@@ -1,19 +1,26 @@
"""
Anthropic/Claude integration module.
Provides model selection with automatic fallback between Claude and Ollama.
Provides model selection with Ollama as primary backend and Claude
as the cloud fallback.
"""
from src.anthropic.model_selector import (
check_claude_health,
check_ollama_health,
get_model,
get_tool_choice_settings,
is_claude_available,
is_ollama_available,
resolve_backend,
)
__all__ = [
"check_claude_health",
"check_ollama_health",
"get_model",
"get_tool_choice_settings",
"is_claude_available",
"is_ollama_available",
"resolve_backend",
]
+146 -22
View File
@@ -1,23 +1,84 @@
"""
Model selector for Claude/Ollama backend switching.
Model selector for Ollama/Claude backend switching.
Provides automatic model selection with Claude as preferred backend
and Ollama as offline fallback.
Provides automatic model selection with Ollama as the primary local backend
and Claude as the cloud fallback. Claude is used when PREFER_CLOUD_BACKEND
is enabled, or automatically when Ollama is unavailable at startup.
The Anthropic SDK is imported lazily so a missing or broken `anthropic`
package degrades to Ollama-only operation instead of crashing the app.
"""
from typing import Union
from __future__ import annotations
from pydantic_ai.models.anthropic import AnthropicModel
from pydantic_ai.models.openai import OpenAIChatModel
from pydantic_ai.providers.anthropic import AnthropicProvider
from typing import TYPE_CHECKING
import httpx
from src.core.config import config
from src.core.logging_config import get_logger
if TYPE_CHECKING:
from pydantic_ai.models.anthropic import AnthropicModel
from pydantic_ai.models.openai import OpenAIChatModel
from pydantic_ai.settings import ModelSettings
logger = get_logger(__name__)
# Cached health check result (set once at startup)
# Cached health check results (set once at startup)
_claude_available: bool | None = None
_ollama_available: bool | None = None
async def check_ollama_health() -> bool:
"""
Check if the Ollama server is reachable and has the configured model.
This should be called once at application startup.
The result is cached in `_ollama_available`.
Returns:
True if Ollama is reachable and OLLAMA_DEFAULT_MODEL is pulled.
"""
global _ollama_available
host = str(config.OLLAMA_HOST).rstrip("/")
model = config.OLLAMA_DEFAULT_MODEL
try:
async with httpx.AsyncClient(timeout=5.0) as client:
response = await client.get(f"{host}/api/tags")
response.raise_for_status()
names = [m.get("name", "") for m in response.json().get("models", [])]
if model in names or f"{model}:latest" in names:
_ollama_available = True
logger.info(
"ollama_health_check_passed",
host=host,
model=model,
)
return True
_ollama_available = False
logger.warning(
"ollama_health_check_failed",
reason="model_not_pulled",
host=host,
model=model,
hint=f"run `ollama pull {model}`",
)
return False
except Exception as e:
_ollama_available = False
logger.warning(
"ollama_health_check_failed",
reason="server_unreachable",
host=host,
error=str(e),
)
return False
async def check_claude_health() -> bool:
@@ -85,28 +146,69 @@ def is_claude_available() -> bool:
return _claude_available is True
def get_model(prefer_cloud: bool | None = None) -> Union[AnthropicModel, OpenAIChatModel]:
def is_ollama_available() -> bool:
"""
Check if Ollama is available (from cached health check result).
Returns:
False only if the startup health check confirmed Ollama is down.
Unknown (check not run yet) counts as available so that contexts
without lifespan events keep the local-first behavior.
"""
return _ollama_available is not False
def resolve_backend(prefer_cloud: bool | None = None) -> str:
"""
Resolve which backend should serve requests.
Ollama is the primary backend. Claude is used when explicitly
preferred via PREFER_CLOUD_BACKEND, or as automatic fallback
when the startup health check found Ollama down.
Args:
prefer_cloud: Override config.PREFER_CLOUD_BACKEND for this call.
Returns:
"claude" or "ollama".
"""
use_cloud = prefer_cloud if prefer_cloud is not None else config.PREFER_CLOUD_BACKEND
if use_cloud and is_claude_available():
return "claude"
if not is_ollama_available() and is_claude_available():
logger.warning(
"backend_fallback_to_claude",
reason="ollama_unavailable",
)
return "claude"
return "ollama"
def get_model(prefer_cloud: bool | None = None) -> AnthropicModel | OpenAIChatModel:
"""
Get the best available model.
Returns Claude if available and preferred, otherwise Ollama.
Returns Ollama unless Claude is preferred (or Ollama is down).
Args:
prefer_cloud: Override config.PREFER_CLOUD_BACKEND for this call.
If None, uses the config value.
Returns:
PydanticAI model instance (AnthropicModel or OpenAIChatModel).
PydanticAI model instance (OpenAIChatModel or AnthropicModel).
Example:
>>> model = get_model()
>>> agent = Agent(model, system_prompt="...")
"""
# Determine preference
use_cloud = prefer_cloud if prefer_cloud is not None else config.PREFER_CLOUD_BACKEND
if resolve_backend(prefer_cloud) == "claude":
try:
from pydantic_ai.models.anthropic import AnthropicModel
from pydantic_ai.providers.anthropic import AnthropicProvider
# Use Claude if available and preferred
if use_cloud and is_claude_available():
logger.debug(
"model_selected",
backend="claude",
@@ -116,15 +218,21 @@ def get_model(prefer_cloud: bool | None = None) -> Union[AnthropicModel, OpenAIC
model_name=config.ANTHROPIC_MODEL,
provider=AnthropicProvider(api_key=config.ANTHROPIC_API_KEY),
)
except ImportError as e:
logger.error(
"claude_backend_import_failed",
error=str(e),
hint="anthropic package missing or incompatible; using Ollama",
)
from pydantic_ai.models.openai import OpenAIChatModel
# Fall back to Ollama
from src.ollama.provider import get_ollama_provider
logger.debug(
"model_selected",
backend="ollama",
model=config.OLLAMA_DEFAULT_MODEL,
reason="fallback" if use_cloud else "preferred_local",
)
return OpenAIChatModel(
model_name=config.OLLAMA_DEFAULT_MODEL,
@@ -132,7 +240,7 @@ def get_model(prefer_cloud: bool | None = None) -> Union[AnthropicModel, OpenAIC
)
def get_tool_choice_settings() -> 'ModelSettings':
def get_tool_choice_settings() -> ModelSettings:
"""
Get model_settings for forcing tool calls on the first request.
@@ -141,7 +249,7 @@ def get_tool_choice_settings() -> 'ModelSettings':
"""
from pydantic_ai.settings import ModelSettings
if is_claude_available() and config.PREFER_CLOUD_BACKEND:
if resolve_backend() == "claude":
# PydanticAI's Anthropic model handles tool_choice internally
return ModelSettings()
else:
@@ -149,6 +257,20 @@ def get_tool_choice_settings() -> 'ModelSettings':
return ModelSettings(extra_body={"tool_choice": "required"})
def get_sampling_settings(temperature: float) -> ModelSettings:
"""
Get model_settings with a sampling temperature where the backend allows it.
Ollama accepts a temperature; Claude Sonnet 5+ rejects sampling
parameters, so the Claude backend gets empty settings.
"""
from pydantic_ai.settings import ModelSettings
if resolve_backend() == "claude":
return ModelSettings()
return ModelSettings(temperature=temperature)
def get_model_info() -> dict:
"""
Get information about the current model configuration.
@@ -158,12 +280,14 @@ def get_model_info() -> dict:
Returns:
Dict with backend, model name, and availability info.
"""
use_cloud = config.PREFER_CLOUD_BACKEND and is_claude_available()
backend = resolve_backend()
return {
"backend": "claude" if use_cloud else "ollama",
"model": config.ANTHROPIC_MODEL if use_cloud else config.OLLAMA_DEFAULT_MODEL,
"backend": backend,
"model": config.ANTHROPIC_MODEL if backend == "claude" else config.OLLAMA_DEFAULT_MODEL,
"claude_available": is_claude_available(),
"claude_configured": bool(config.ANTHROPIC_API_KEY),
"ollama_available": is_ollama_available(),
"ollama_model": config.OLLAMA_DEFAULT_MODEL,
"prefer_cloud": config.PREFER_CLOUD_BACKEND,
}
+11 -7
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@@ -64,21 +64,21 @@ class Config(BaseSettings):
API_PORT: int = Field(default=8000, description="API port")
API_PREFIX: str = Field(default="/v1", description="API route prefix")
# Anthropic Configuration (Claude - preferred backend)
# Anthropic Configuration (Claude - cloud fallback)
ANTHROPIC_API_KEY: str | None = Field(
default=None,
description="Anthropic API key for Claude access"
description="Anthropic API key for the Claude fallback backend"
)
ANTHROPIC_MODEL: str = Field(
default="claude-sonnet-4-20250514",
description="Claude model to use"
default="claude-sonnet-5",
description="Claude model for the fallback backend"
)
PREFER_CLOUD_BACKEND: bool = Field(
default=True,
description="Prefer Claude over Ollama when available"
default=False,
description="Prefer Claude over Ollama (default: local-first)"
)
# Ollama Configuration (local fallback)
# Ollama Configuration (local - primary backend)
OLLAMA_HOST: HttpUrl = Field(
default="http://localhost:11434",
description="Ollama server URL"
@@ -91,6 +91,10 @@ class Config(BaseSettings):
default=120,
description="Ollama request timeout in seconds"
)
STEWARD_TIMEOUT: int = Field(
default=60,
description="Steward analysis timeout in seconds (gemma4 needs ~35s warm)"
)
STREAM_TIMEOUT: int = Field(
default=20,
description="Timeout for each streaming turn in seconds"
+9 -3
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@@ -9,7 +9,11 @@ from src.agents.biographer import register_biographer
from src.agents.housekeeper import register_housekeeper
from src.agents.librarian import register_librarian
from src.agents.tatlock_core import TATLOCK_CORE_CAPABILITY, tatlock_core_tools
from src.anthropic.model_selector import check_claude_health, get_model_info
from src.anthropic.model_selector import (
check_claude_health,
check_ollama_health,
get_model_info,
)
from src.core.household_registry import get_household_registry
from src.core.logging_config import get_logger
@@ -87,7 +91,7 @@ async def initialize_application():
Initialize the application.
Performs all startup tasks:
1. Check Claude API health (for backend selection)
1. Check Ollama (primary) and Claude (fallback) health for backend selection
2. Register household members
3. (Future) Initialize connections
@@ -95,13 +99,15 @@ async def initialize_application():
"""
logger.info("application_initialization_starting")
# Check Claude API health for backend selection
# Check backend health: Ollama is primary, Claude is the fallback
await check_ollama_health()
await check_claude_health()
model_info = get_model_info()
logger.info(
"model_backend_configured",
backend=model_info["backend"],
model=model_info["model"],
ollama_available=model_info["ollama_available"],
claude_available=model_info["claude_available"],
)
+3 -1
View File
@@ -410,10 +410,12 @@ async def test_tatlock_ollama_fallback(async_client: AsyncClient):
"stream": False
}
# 300s: this test forbids the Claude rescue, and the full local
# Steward -> orchestrate -> synthesize flow on gemma4 exceeds 120s
response = await async_client.post(
"/v1/chat/completions",
json=request_data,
timeout=120.0
timeout=300.0
)
assert response.status_code == 200
View File
+92
View File
@@ -0,0 +1,92 @@
"""
Unit tests for backend selection (Ollama primary, Claude fallback).
These tests set the cached health-check globals directly so they are
deterministic regardless of which services are reachable.
"""
import pytest
from src.anthropic import model_selector
from src.core.config import config
@pytest.fixture
def local_first(monkeypatch):
"""Baseline: local-first config, both backends healthy."""
monkeypatch.setattr(config, "PREFER_CLOUD_BACKEND", False)
monkeypatch.setattr(config, "ANTHROPIC_API_KEY", "sk-test-fake")
monkeypatch.setattr(model_selector, "_claude_available", True)
monkeypatch.setattr(model_selector, "_ollama_available", True)
class TestResolveBackend:
def test_default_is_ollama(self, local_first):
assert model_selector.resolve_backend() == "ollama"
def test_prefer_cloud_config_selects_claude(self, local_first, monkeypatch):
monkeypatch.setattr(config, "PREFER_CLOUD_BACKEND", True)
assert model_selector.resolve_backend() == "claude"
def test_prefer_cloud_override_selects_claude(self, local_first):
assert model_selector.resolve_backend(prefer_cloud=True) == "claude"
def test_prefer_cloud_without_claude_falls_back_to_ollama(self, local_first, monkeypatch):
monkeypatch.setattr(config, "PREFER_CLOUD_BACKEND", True)
monkeypatch.setattr(model_selector, "_claude_available", False)
assert model_selector.resolve_backend() == "ollama"
def test_ollama_down_falls_back_to_claude(self, local_first, monkeypatch):
monkeypatch.setattr(model_selector, "_ollama_available", False)
assert model_selector.resolve_backend() == "claude"
def test_ollama_down_without_claude_stays_ollama(self, local_first, monkeypatch):
monkeypatch.setattr(model_selector, "_ollama_available", False)
monkeypatch.setattr(model_selector, "_claude_available", False)
assert model_selector.resolve_backend() == "ollama"
def test_unknown_ollama_state_counts_as_available(self, local_first, monkeypatch):
monkeypatch.setattr(model_selector, "_ollama_available", None)
assert model_selector.resolve_backend() == "ollama"
class TestGetModel:
def test_ollama_backend_returns_openai_chat_model(self, local_first):
from pydantic_ai.models.openai import OpenAIChatModel
model = model_selector.get_model()
assert isinstance(model, OpenAIChatModel)
assert model.model_name == config.OLLAMA_DEFAULT_MODEL
def test_claude_backend_returns_anthropic_model(self, local_first):
from pydantic_ai.models.anthropic import AnthropicModel
model = model_selector.get_model(prefer_cloud=True)
assert isinstance(model, AnthropicModel)
assert model.model_name == config.ANTHROPIC_MODEL
class TestToolChoiceSettings:
def test_ollama_forces_tool_choice(self, local_first):
settings = model_selector.get_tool_choice_settings()
assert settings.get("extra_body") == {"tool_choice": "required"}
def test_claude_uses_native_tool_choice(self, local_first, monkeypatch):
monkeypatch.setattr(config, "PREFER_CLOUD_BACKEND", True)
settings = model_selector.get_tool_choice_settings()
assert not settings.get("extra_body")
class TestGetModelInfo:
def test_reports_ollama_primary(self, local_first):
info = model_selector.get_model_info()
assert info["backend"] == "ollama"
assert info["model"] == config.OLLAMA_DEFAULT_MODEL
assert info["ollama_available"] is True
assert info["claude_available"] is True
assert info["prefer_cloud"] is False
def test_reports_claude_when_ollama_down(self, local_first, monkeypatch):
monkeypatch.setattr(model_selector, "_ollama_available", False)
info = model_selector.get_model_info()
assert info["backend"] == "claude"
assert info["model"] == config.ANTHROPIC_MODEL