Restructure pydantic_ai utils into LlamaStack model and provider classes

Move llama_stack_provider_from_client and _model_settings_from_responses_params
out of utils/pydantic_ai.py into their owning classes as static factory methods:
- LlamaStackProvider.from_llama_stack_client() in _provider.py
- LlamaStackResponsesModel.from_llama_stack_client() in _model.py
- _model_settings_from_responses_params and _LLS_RESPONSES_EXTRA_FIELDS into _model.py

Update callers (QuestionValidity, build_agent) to use the new factory methods
and relocate corresponding tests to test_model.py and test_provider.py.

Author: Jazzcort

src/pydantic_ai_lightspeed/capabilities/question_validity/_capability.py

@@ -27,7 +27,6 @@
     QuestionValidityConfig,
 )
 from pydantic_ai_lightspeed.llamastack import LlamaStackResponsesModel
-from utils.pydantic_ai import llama_stack_provider_from_client
 
 logger = get_logger(__name__)
 
@@ -55,21 +54,6 @@ def _extract_message_str_from_user_content(user_content: Sequence[UserContent])
     return "\n".join(str_arr)
 
 
-def _create_model_from_llama_stack_client(model_id: str) -> LlamaStackResponsesModel:
-    """Create a LlamaStackResponsesModel from the shared Llama Stack client.
-
-    Parameters:
-        model_id: The model identifier to use for the responses model.
-
-    Returns:
-        A configured LlamaStackResponsesModel instance.
-    """
-    client = AsyncLlamaStackClientHolder().get_client()
-    provider = llama_stack_provider_from_client(client)
-    settings = OpenAIResponsesModelSettings(openai_store=False)
-    return LlamaStackResponsesModel(model_id, provider=provider, settings=settings)
-
-
 @dataclass
 class QuestionValidity(AbstractCapability[None]):
     """Block or modify user input based on a guardrail check.
@@ -91,7 +75,13 @@ class QuestionValidity(AbstractCapability[None]):
 
     def __post_init__(self) -> None:
         """Initialize the model instance from the configured model ID."""
-        self._model = _create_model_from_llama_stack_client(self.config.model_id)
+        llama_stack_client = AsyncLlamaStackClientHolder().get_client()
+
+        self._model = LlamaStackResponsesModel.from_llama_stack_client(
+            self.config.model_id,
+            llama_stack_client,
+            model_settings=OpenAIResponsesModelSettings(openai_store=False),
+        )
 
     def _build_prompt(self, message: str | Sequence[UserContent] | None) -> str:
         """Build the classification prompt from the user message.

src/pydantic_ai_lightspeed/llamastack/_model.py

@@ -19,8 +19,10 @@
 from collections import defaultdict
 from collections.abc import AsyncIterator
 from contextlib import asynccontextmanager
-from typing import Any, cast
+from typing import Any, Final, cast
 
+from llama_stack.core.library_client import AsyncLlamaStackAsLibraryClient
+from llama_stack_client import AsyncLlamaStackClient
 from openai import AsyncStream
 from openai.types import responses
 from pydantic_ai import UnexpectedModelBehavior
@@ -38,12 +40,56 @@
     OpenAIResponsesStreamedResponse,
     _map_api_errors,
 )
+from pydantic_ai.profiles import ModelProfileSpec
 from pydantic_ai.settings import ModelSettings
 
 from log import get_logger
+from models.common.responses.responses_api_params import ResponsesApiParams
+from pydantic_ai_lightspeed.llamastack._provider import LlamaStackProvider
 
 logger = get_logger(__name__)
 
+_LLS_RESPONSES_EXTRA_FIELDS: Final[frozenset[str]] = frozenset(
+    {
+        "conversation",
+        "max_infer_iters",
+        "tools",
+        "tool_choice",
+        "include",
+        "text",
+        "reasoning",
+        "prompt",
+        "metadata",
+        "max_tool_calls",
+        "safety_identifier",
+    }
+)
+
+
+def _model_settings_from_responses_params(
+    responses_params: ResponsesApiParams,
+) -> OpenAIResponsesModelSettings:
+    """Map ``ResponsesApiParams`` into Pydantic AI OpenAI Responses model settings."""
+    payload = responses_params.model_dump(exclude_none=True)
+    extra_body = {k: v for k, v in payload.items() if k in _LLS_RESPONSES_EXTRA_FIELDS}
+    settings_dict: dict[str, Any] = {}
+    if extra_body:
+        settings_dict["extra_body"] = extra_body
+    if responses_params.max_output_tokens is not None:
+        settings_dict["max_tokens"] = responses_params.max_output_tokens
+    if responses_params.temperature is not None:
+        settings_dict["temperature"] = responses_params.temperature
+    if responses_params.parallel_tool_calls is not None:
+        settings_dict["parallel_tool_calls"] = responses_params.parallel_tool_calls
+    if responses_params.extra_headers:
+        settings_dict["extra_headers"] = dict(responses_params.extra_headers)
+    settings_dict["openai_store"] = responses_params.store
+    if responses_params.previous_response_id is not None:
+        settings_dict["openai_previous_response_id"] = (
+            responses_params.previous_response_id
+        )
+    return cast(OpenAIResponsesModelSettings, settings_dict)
+
 
 class _FilteredResponseStream:
     """Wraps an OpenAI AsyncStream to reorder spurious events from Llama Stack.
@@ -307,3 +353,53 @@ async def request_stream(  # pylint: disable=unused-argument
                     else None
                 ),
             )
+
+    @staticmethod
+    def from_llama_stack_client(
+        model_name: str,
+        client: AsyncLlamaStackClient | AsyncLlamaStackAsLibraryClient,
+        *,
+        responses_params: ResponsesApiParams | None = None,
+        model_settings: ModelSettings | None = None,
+        profile: ModelProfileSpec | None = None,
+    ) -> LlamaStackResponsesModel:
+        """Create a ``LlamaStackResponsesModel`` from a Llama Stack client.
+
+        Mirrors ``OpenAIResponsesModel.__init__`` parameters, but accepts a
+        Llama Stack client instead of a provider.  Exactly one of
+        ``responses_params`` or ``model_settings`` may be provided.
+
+        Args:
+            model_name: The model name/ID to use.
+            client: Llama Stack client to build the provider from.
+            responses_params: Optional ``ResponsesApiParams``, converted to
+                ``OpenAIResponsesModelSettings`` internally.  Mutually
+                exclusive with ``model_settings``.
+            model_settings: Optional raw ``ModelSettings`` passed through
+                directly.  Mutually exclusive with ``responses_params``.
+            profile: Optional model profile specification.
+
+        Raises:
+            ValueError: If both ``responses_params`` and ``model_settings``
+                are provided.
+
+        Returns:
+            Configured ``LlamaStackResponsesModel`` instance.
+        """
+        provider = LlamaStackProvider.from_llama_stack_client(client)
+
+        if responses_params is not None and model_settings is not None:
+            raise ValueError(
+                "You can only pass either ResponsesApiParams or ModelSetting not both."
+            )
+
+        _settings: OpenAIResponsesModelSettings | ModelSettings | None = None
+
+        if responses_params is not None:
+            _settings = _model_settings_from_responses_params(responses_params)
+        elif model_settings is not None:
+            _settings = model_settings
+
+        return LlamaStackResponsesModel(
+            model_name, provider=provider, profile=profile, settings=_settings
+        )

src/pydantic_ai_lightspeed/llamastack/_provider.py

@@ -5,6 +5,8 @@
 from typing import TYPE_CHECKING, Optional
 
 import httpx
+from llama_stack.core.library_client import AsyncLlamaStackAsLibraryClient
+from llama_stack_client import AsyncLlamaStackClient
 from openai import AsyncOpenAI
 from pydantic_ai import ModelProfile
 from pydantic_ai.models import create_async_http_client
@@ -14,7 +16,9 @@
 from pydantic_ai_lightspeed.llamastack._transport import LlamaStackLibraryTransport
 
 if TYPE_CHECKING:
-    from llama_stack.core.library_client import AsyncLlamaStackAsLibraryClient
+    from llama_stack.core.library_client import (
+        AsyncLlamaStackAsLibraryClient,  # pylint: disable=reimported
+    )
 
 DEFAULT_BASE_URL = "http://localhost:8321/v1"
 
@@ -48,6 +52,33 @@ def model_profile(model_name: str) -> Optional[ModelProfile]:
         """Return the model profile for the named model, if available."""
         return openai_model_profile(model_name)
 
+    @staticmethod
+    def from_llama_stack_client(
+        client: AsyncLlamaStackClient | AsyncLlamaStackAsLibraryClient,
+    ) -> LlamaStackProvider:
+        """Create a ``LlamaStackProvider`` from a Llama Stack client.
+
+        For an ``AsyncLlamaStackAsLibraryClient``, delegates to library mode.
+        For an ``AsyncLlamaStackClient``, extracts the base URL, API key, and
+        underlying HTTP client to create a server-mode provider.
+
+        Args:
+            client: A Llama Stack client (server or library variant).
+
+        Returns:
+            Configured ``LlamaStackProvider`` instance.
+        """
+        if isinstance(client, AsyncLlamaStackAsLibraryClient):
+            return LlamaStackProvider(library_client=client)
+        api_key = client.api_key or "not-needed"
+        base = str(client.base_url).rstrip("/")
+        base_url = base if base.endswith("/v1") else f"{base}/v1"
+        return LlamaStackProvider(
+            base_url=base_url,
+            api_key=api_key,
+            http_client=client._client,  # pylint: disable=protected-access
+        )
+
     def __init__(
         self,
         *,

src/utils/pydantic_ai.py

@@ -2,80 +2,20 @@
 
 from __future__ import annotations
 
-from typing import Any, Final, Optional, cast
+from typing import Optional
 
 from llama_stack.core.library_client import AsyncLlamaStackAsLibraryClient
 from llama_stack_client import AsyncLlamaStackClient
 from pydantic_ai.agent import Agent
 from pydantic_ai.capabilities import AbstractCapability, AgentCapability
-from pydantic_ai.models.openai import OpenAIResponsesModelSettings
 from pydantic_ai_skills import SkillsCapability
 
 from models.common.responses.responses_api_params import ResponsesApiParams
 from models.config import SkillsConfiguration
 from pydantic_ai_lightspeed.llamastack import (
-    LlamaStackProvider,
     LlamaStackResponsesModel,
 )
 
-_LLS_RESPONSES_EXTRA_FIELDS: Final[frozenset[str]] = frozenset(
-    {
-        "conversation",
-        "max_infer_iters",
-        "tool_choice",
-        "include",
-        "text",
-        "reasoning",
-        "prompt",
-        "metadata",
-        "max_tool_calls",
-        "safety_identifier",
-    }
-)
-
-
-def llama_stack_provider_from_client(
-    client: AsyncLlamaStackClient | AsyncLlamaStackAsLibraryClient,
-) -> LlamaStackProvider:
-    """Construct a Pydantic AI Llama Stack provider backed by the same client as ``/query``."""
-    if isinstance(client, AsyncLlamaStackAsLibraryClient):
-        return LlamaStackProvider(library_client=client)
-    api_key = client.api_key or "not-needed"
-    base = str(client.base_url).rstrip("/")
-    base_url = base if base.endswith("/v1") else f"{base}/v1"
-    return LlamaStackProvider(
-        base_url=base_url,
-        api_key=api_key,
-        http_client=client._client,  # pylint: disable=protected-access
-    )
-
-
-def _model_settings_from_responses_params(
-    responses_params: ResponsesApiParams,
-) -> OpenAIResponsesModelSettings:
-    """Map ``ResponsesApiParams`` into Pydantic AI OpenAI Responses model settings."""
-    payload = responses_params.model_dump(exclude_none=True)
-    extra_body = {k: v for k, v in payload.items() if k in _LLS_RESPONSES_EXTRA_FIELDS}
-    settings_dict: dict[str, Any] = {}
-    if extra_body:
-        settings_dict["extra_body"] = extra_body
-    if responses_params.max_output_tokens is not None:
-        settings_dict["max_tokens"] = responses_params.max_output_tokens
-    if responses_params.temperature is not None:
-        settings_dict["temperature"] = responses_params.temperature
-    if responses_params.parallel_tool_calls is not None:
-        settings_dict["parallel_tool_calls"] = responses_params.parallel_tool_calls
-    if responses_params.extra_headers:
-        settings_dict["extra_headers"] = dict(responses_params.extra_headers)
-    settings_dict["openai_store"] = responses_params.store
-    if responses_params.tools is not None:
-        settings_dict["openai_native_tools"] = responses_params.tools
-    if responses_params.previous_response_id is not None:
-        settings_dict["openai_previous_response_id"] = (
-            responses_params.previous_response_id
-        )
-    return cast(OpenAIResponsesModelSettings, settings_dict)
-
 
 def _skills_capability(
     skills_config: Optional[SkillsConfiguration],
@@ -147,15 +87,12 @@ def build_agent(
         ``Agent`` configured for ``await agent.run(...)`` (or streaming) against the same
         stack configuration as ``client.responses.create(**responses_params.model_dump())``.
     """
-    provider = llama_stack_provider_from_client(client)
-    settings = _model_settings_from_responses_params(responses_params)
     capabilities = _agent_capabilities(skills, no_tools=no_tools)
 
-    model = LlamaStackResponsesModel(
-        responses_params.model,
-        provider=provider,
-        settings=settings,
+    model = LlamaStackResponsesModel.from_llama_stack_client(
+        responses_params.model, client, responses_params=responses_params
     )
+
     return Agent(
         model,
         instructions=responses_params.instructions,