fix(llm): bind dedupe credentials to a provider; send reasoning=max via extra_body (#1187)

Co-authored-by: Ahmed Allam <ahmed39652003@gmail.com>

strix/config/models.py

@@ -18,7 +18,7 @@ from agents import (
 )
 from agents.model_settings import ModelSettings
 from agents.models.fake_id import FAKE_RESPONSES_ID
-from agents.models.interface import Model
+from agents.models.interface import Model, ModelProvider
 from agents.models.multi_provider import MultiProvider
 from agents.models.openai_responses import OpenAIResponsesModel
 from agents.retry import (
@@ -48,7 +48,7 @@ if TYPE_CHECKING:
     from agents.agent_output import AgentOutputSchemaBase
     from agents.handoffs import Handoff
     from agents.items import ModelResponse, TResponseInputItem, TResponseStreamEvent
-    from agents.models.interface import ModelProvider, ModelTracing
+    from agents.models.interface import ModelTracing
     from agents.retry import ModelRetryAdvice, ModelRetryAdviceRequest
     from agents.tool import Tool
     from agents.usage import Usage
@@ -445,12 +445,61 @@ def _response_usage(usage: Usage | None) -> ResponseUsage | None:
     )
 
 
+class _CredentialedLitellmProvider(ModelProvider):
+    """LiteLLM route bound to one endpoint's credentials.
+
+    ``LitellmProvider`` reads them from the process-wide LiteLLM globals, which
+    belong to the main model; a secondary endpoint needs its own.
+    """
+
+    def __init__(self, api_key: str | None, base_url: str | None) -> None:
+        self._api_key = api_key
+        self._base_url = base_url
+
+    def get_model(self, model_name: str | None) -> Model:
+        from agents.extensions.models.litellm_model import LitellmModel
+        from agents.models.default_models import get_default_model
+
+        return LitellmModel(
+            model=model_name or get_default_model(),
+            api_key=self._api_key,
+            base_url=self._base_url,
+        )
+
+
 class StrixProvider(MultiProvider):
     """Route any non-OpenAI prefix through LiteLLM with the prefix preserved,
     so users type ``deepseek/deepseek-chat`` rather than
     ``litellm/deepseek/deepseek-chat``.
+
+    ``api_key``/``base_url`` bind every route this provider resolves to one
+    endpoint, for a secondary model (the dedupe judge) whose endpoint differs
+    from the main model's process-wide defaults.
     """
 
+    def __init__(
+        self,
+        *,
+        api_key: str | None = None,
+        base_url: str | None = None,
+        **kwargs: Any,
+    ) -> None:
+        super().__init__(
+            openai_api_key=api_key,
+            openai_base_url=base_url,
+            # A custom endpoint is OpenAI-compatible, i.e. chat completions; the
+            # global default is the main model's and may say otherwise.
+            openai_use_responses=False if base_url else None,
+            **kwargs,
+        )
+        self._override_api_key = api_key
+        self._override_base_url = base_url
+
+    def _create_fallback_provider(self, prefix: str) -> ModelProvider:
+        if prefix == "litellm" and (self._override_api_key or self._override_base_url):
+            return _CredentialedLitellmProvider(self._override_api_key, self._override_base_url)
+        return super()._create_fallback_provider(prefix)
+
     def _resolve_prefixed_model(
         self,
         *,

strix/core/inputs.py

@@ -268,7 +268,7 @@ def make_model_settings(
         and model_supports_reasoning(model_name)
     ):
         model_settings = model_settings.resolve(
-            _reasoning_settings(reasoning_effort, model_settings.extra_args),
+            _reasoning_settings(reasoning_effort),
         )
     if force_required_tool_choice and _accepts_required_tool_choice(model_name):
         model_settings = model_settings.resolve(ModelSettings(tool_choice="required"))
@@ -294,20 +294,19 @@ def _request_headers(
     return headers or None
 
 
-def _reasoning_settings(
-    effort: ReasoningEffort,
-    extra_args: dict[str, Any] | None,
-) -> ModelSettings:
+def _reasoning_settings(effort: ReasoningEffort) -> ModelSettings:
     """``max`` is not in the OpenAI SDK's ``Reasoning.effort`` enum, so send it as
     a raw body field instead — also keeping it clear of LiteLLM's DeepSeek mapping,
     which collapses every ``reasoning_effort`` level to plain thinking-enabled.
     Providers that don't support ``max`` reject the request.
+
+    It goes in ``extra_body``, the field every model implementation forwards as the
+    request's ``extra_body``; the same value under ``extra_args`` collides with that
+    keyword and raises before a request is ever sent.
     """
     if effort != "max":
         return ModelSettings(reasoning=Reasoning(effort=effort))
-    return ModelSettings(
-        extra_args={**(extra_args or {}), "extra_body": {"reasoning_effort": "max"}},
-    )
+    return ModelSettings(extra_body={"reasoning_effort": "max"})
 
 
 def _prompt_cache_extra_args(model_name: str) -> dict[str, Any] | None:

strix/interface/main.py

@@ -127,12 +127,10 @@ def _subscription_error_hint(exc: BaseException) -> str | None:
 
 
 async def warm_up_llm(show_model_warning: bool = True) -> None:
-    from agents.model_settings import ModelSettings
     from agents.models.interface import ModelTracing
 
     from strix.config.models import (
         RECOMMENDED_MODEL_NAMES,
-        StrixProvider,
         configure_sdk_model_defaults,
         is_known_openai_bare_model,
         is_recommended_or_frontier_model,
@@ -209,12 +207,11 @@ async def warm_up_llm(show_model_warning: bool = True) -> None:
         logger.info("LLM warm-up succeeded for model %s", (llm.model or "").strip())
 
         if settings.dedupe.model:
-            from strix.report.dedupe import _dedupe_extra_args
+            from strix.report.dedupe import resolve_dedupe_model
 
             dedupe_model = settings.dedupe.model.strip()
             raw_model = dedupe_model
-            deduper = StrixProvider().get_model(dedupe_model)
-            deduper_extra = _dedupe_extra_args(settings.dedupe)
+            deduper = resolve_dedupe_model(settings.dedupe, dedupe_model)
             # A dedicated dedupe model may route to another provider, which must
             # never receive the main endpoint's headers; it has its own
             # DEDUPE_LLM_EXTRA_HEADERS.
@@ -226,9 +223,6 @@ async def warm_up_llm(show_model_warning: bool = True) -> None:
                 extra_headers=settings.dedupe.extra_headers,
                 has_tools=False,
             )
-            if deduper_extra:
-                merged = {**(deduper_settings.extra_args or {}), **deduper_extra}
-                deduper_settings = deduper_settings.resolve(ModelSettings(extra_args=merged))
             await asyncio.wait_for(
                 deduper.get_response(
                     system_instructions="You are a helpful assistant.",

strix/report/dedupe.py

@@ -7,7 +7,6 @@ import logging
 import re
 from typing import TYPE_CHECKING, Any
 
-from agents.model_settings import ModelSettings
 from agents.models.interface import ModelTracing
 from openai.types.responses import ResponseOutputMessage
 
@@ -22,6 +21,8 @@ from strix.report.state import get_global_report_state
 
 if TYPE_CHECKING:
     from agents.items import ModelResponse
+    from agents.model_settings import ModelSettings
+    from agents.models.interface import Model
 
     from strix.config.settings import DedupeSettings
 
@@ -29,30 +30,11 @@ if TYPE_CHECKING:
 logger = logging.getLogger(__name__)
 
 
-def _dedupe_extra_args(dedupe: DedupeSettings) -> dict[str, str]:
-    """Per-call credential + endpoint for the dedupe model.
-
-    Provider env vars and the global base URL are process-wide, so a
-    shared-provider dedupe key or a distinct dedupe endpoint can't be installed
-    globally without clobbering (or being clobbered by) the main model's
-    config. Passing them per call keeps the two apart. Only applies when a
-    dedicated dedupe model is configured.
-    """
-    if not dedupe.model:
-        return {}
-    extra: dict[str, str] = {}
-    if dedupe.api_key and dedupe.api_key.strip():
-        extra["api_key"] = dedupe.api_key.strip()
-    if dedupe.api_base and dedupe.api_base.strip():
-        extra["api_base"] = dedupe.api_base.strip()
-    return extra
-
-
 def _dedupe_model_settings(
     dedupe: DedupeSettings, model_name: str, request_timeout: float | None
 ) -> ModelSettings:
     llm = load_settings().llm
-    settings = make_model_settings(
+    return make_model_settings(
         dedupe.reasoning_effort,
         model_name=model_name,
         force_required_tool_choice=False,
@@ -64,10 +46,21 @@ def _dedupe_model_settings(
         extra_headers=dedupe.extra_headers if dedupe.model else llm.extra_headers,
         has_tools=False,
     )
-    extra = _dedupe_extra_args(dedupe)
-    if extra:
-        settings = settings.resolve(ModelSettings(extra_args=extra))
-    return settings
+
+
+def resolve_dedupe_model(dedupe: DedupeSettings, model_name: str) -> Model:
+    """Resolve the dedupe model, bound to its own endpoint when it has one.
+
+    Credentials can't ride on the request: every model implementation already
+    passes its own ``api_key``/``base_url``, so the same keys in ``extra_args``
+    collide with them and raise before anything is sent. A provider bound to the
+    dedupe endpoint keeps it apart from the main model's process-wide defaults.
+    """
+    api_key = (dedupe.api_key or "").strip() if dedupe.model else ""
+    api_base = (dedupe.api_base or "").strip() if dedupe.model else ""
+    if not (api_key or api_base):
+        return StrixProvider().get_model(model_name)
+    return StrixProvider(api_key=api_key or None, base_url=api_base or None).get_model(model_name)
 
 
 DEDUPE_SYSTEM_PROMPT = """You are an expert vulnerability report deduplication judge.
@@ -371,7 +364,7 @@ async def check_duplicate(
 
         configure_sdk_model_defaults(settings)
         resolved_model = model_name.strip()
-        model = StrixProvider().get_model(resolved_model)
+        model = resolve_dedupe_model(dedupe, resolved_model)
         response = await model.get_response(
             system_instructions=DEDUPE_SYSTEM_PROMPT,
             input=user_msg,

tests/test_dedupe_model.py

@@ -7,7 +7,7 @@ from typing import TYPE_CHECKING
 
 from strix.config import loader
 from strix.config.settings import DedupeSettings
-from strix.report.dedupe import _dedupe_model_settings
+from strix.report.dedupe import _dedupe_model_settings, resolve_dedupe_model
 
 
 if TYPE_CHECKING:
@@ -16,32 +16,49 @@ if TYPE_CHECKING:
     import pytest
 
 
-def test_dedupe_key_sent_per_call_not_via_global_env() -> None:
+def _unwrap(model: object) -> object:
+    while hasattr(model, "_inner"):
+        model = model._inner
+    return model
+
+
+def test_dedupe_key_bound_to_model_client_not_global_env() -> None:
     dedupe = DedupeSettings(STRIX_DEDUPE_MODEL="deepseek/cheap", DEDUPE_LLM_API_KEY="dedupe-key")
-    settings = _dedupe_model_settings(dedupe, "deepseek/cheap", 300)
-    # The key rides on the request, so a shared-provider main key can't clobber
-    # it (and vice versa) through the global provider env var.
-    assert (settings.extra_args or {})["api_key"] == "dedupe-key"
+    model = _unwrap(resolve_dedupe_model(dedupe, "deepseek/cheap"))
+    # The key is bound to the dedupe model's own client, so a shared-provider
+    # main key can't clobber it (and vice versa) through the process globals —
+    # and it never rides on the request, where every model implementation's own
+    # api_key kwarg would collide with it.
+    assert model.api_key == "dedupe-key"  # type: ignore[attr-defined]
 
 
-def test_dedupe_settings_omit_api_key_when_unset() -> None:
-    dedupe = DedupeSettings(STRIX_DEDUPE_MODEL="deepseek/cheap")
+def test_dedupe_settings_carry_no_request_credentials() -> None:
+    dedupe = DedupeSettings(
+        STRIX_DEDUPE_MODEL="deepseek/cheap",
+        DEDUPE_LLM_API_KEY="dedupe-key",
+        DEDUPE_LLM_API_BASE="https://dedupe.example/v1",
+    )
     settings = _dedupe_model_settings(dedupe, "deepseek/cheap", 300)
     assert "api_key" not in (settings.extra_args or {})
     assert "api_base" not in (settings.extra_args or {})
 
 
-def test_dedupe_endpoint_sent_per_call() -> None:
+def test_dedupe_endpoint_bound_to_model_client() -> None:
     dedupe = DedupeSettings(
         STRIX_DEDUPE_MODEL="openai/cheap",
         DEDUPE_LLM_API_KEY="dedupe-key",
         DEDUPE_LLM_API_BASE="https://dedupe.example/v1",
     )
-    settings = _dedupe_model_settings(dedupe, "openai/cheap", 300)
-    # A distinct dedupe endpoint rides on the request instead of the
-    # process-wide base URL, so it can't clobber the main model's endpoint.
-    assert (settings.extra_args or {})["api_base"] == "https://dedupe.example/v1"
-    assert (settings.extra_args or {})["api_key"] == "dedupe-key"
+    model = _unwrap(resolve_dedupe_model(dedupe, "openai/cheap"))
+    client = model._client  # type: ignore[attr-defined]
+    assert client.api_key == "dedupe-key"
+    assert str(client.base_url).startswith("https://dedupe.example/v1")
+
+
+def test_dedupe_without_credentials_uses_default_provider() -> None:
+    dedupe = DedupeSettings(STRIX_DEDUPE_MODEL="deepseek/cheap")
+    model = _unwrap(resolve_dedupe_model(dedupe, "deepseek/cheap"))
+    assert model.api_key is None  # type: ignore[attr-defined]
 
 
 def test_dedicated_dedupe_model_uses_own_headers_not_main() -> None:

tests/test_inputs.py

@@ -153,7 +153,8 @@ def test_max_reasoning_effort_sent_as_raw_body_field() -> None:
         "max", model_name="deepseek/deepseek-v4-flash", request_timeout=30
     )
     assert settings.reasoning is None
-    assert settings.extra_args == {"timeout": 30, "extra_body": {"reasoning_effort": "max"}}
+    assert settings.extra_args == {"timeout": 30}
+    assert settings.extra_body == {"reasoning_effort": "max"}
 
 
 def test_conversation_tail_breakpoint_moves_with_appended_transcript() -> None: