refactor: extract tooling policy helpers

Move tool allowlist, tool_config, and tooling-context helpers into app/http/tooling_policy.py while keeping route behavior unchanged.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

.omc/handoffs/team-verify.md

@@ -1,6 +1,6 @@
 ## Handoff: team-verify → complete
-- **Decided**: This phase freezes the current tool-call contract instead of expanding runtime behavior: Anthropic forced-tool fallback remains non-stream-only, and streaming keeps raw text when no upstream tool event exists.
-- **Rejected**: No `app/main.py` behavior change, no Anthropic streaming fallback synthesis, and no extra refactor beyond test/schema/docs alignment.
-- **Risks**: README / schema wording must stay aligned with runtime if tool-call support expands later; any future Anthropic streaming fallback work should update both docs and the new regression test together.
-- **Files**: `tests/test_tool_call_bridge.py`, `app/anthropic_schema.py`, `DESIGN.md`, `README.md`
+- **Decided**: This phase only extracts tooling-policy helpers out of `app/main.py` into `app/http/tooling_policy.py`; OpenAI / Anthropic tool allowlist, `tool_config`, and tooling-context behavior stay unchanged.
+- **Rejected**: No protocol/runtime behavior change, no stream/non-stream bridge rewrite, and no session-cache or ask-mode semantic change beyond moving helper definitions.
+- **Risks**: The new helper takes `settings` explicitly, so any future callers must pass the gateway settings object; if tooling policy expands later, keep helper/module boundaries aligned with the existing bridge regression suite.
+- **Files**: `app/main.py`, `app/http/tooling_policy.py`
 - **Remaining**: Run git scope check, create the phase checkpoint commit, push to Gitea, and keep local `main` synced with `origin/main`.

app/http/tooling_policy.py

@@ -0,0 +1,120 @@
+from __future__ import annotations
+
+from typing import Any
+
+from fastapi import HTTPException
+
+from ..anthropic_schema import AnthropicMessagesRequest
+from ..config import Settings
+from ..openai_schema import ChatCompletionsRequest
+from .tool_bridge import (
+    _anthropic_forced_tool_name,
+    _anthropic_tool_name,
+    _openai_forced_tool_name,
+    _openai_tool_name,
+)
+
+
+def _tool_allowlist(settings: Settings) -> set[str]:
+    return {name.strip() for name in settings.tool_allowlist if isinstance(name, str) and name.strip()}
+
+
+def _filter_allowed_tools(
+    tools: list[dict[str, Any]], *, provider: str, settings: Settings
+) -> list[dict[str, Any]]:
+    allowlist = _tool_allowlist(settings)
+    if not allowlist:
+        return tools
+    name_fn = _openai_tool_name if provider == "openai" else _anthropic_tool_name
+    return [tool for tool in tools if (name := name_fn(tool)) and name in allowlist]
+
+
+def _ensure_tool_choice_allowed(tool_choice: Any, *, provider: str, settings: Settings) -> None:
+    allowlist = _tool_allowlist(settings)
+    if not allowlist:
+        return
+    forced_name = (
+        _openai_forced_tool_name(tool_choice)
+        if provider == "openai"
+        else _anthropic_forced_tool_name(tool_choice)
+    )
+    if forced_name and forced_name not in allowlist:
+        raise HTTPException(
+            status_code=400,
+            detail={
+                "error": {
+                    "type": "invalid_request_error",
+                    "message": f"tool '{forced_name}' is not allowed",
+                }
+            },
+        )
+
+
+def _openai_tool_config(req: ChatCompletionsRequest, *, settings: Settings) -> dict[str, Any] | None:
+    if not settings.tool_forward_enabled:
+        return None
+    has_tools = isinstance(req.tools, list) and len(req.tools) > 0
+    has_choice = req.tool_choice is not None
+    if not has_tools and not has_choice:
+        return None
+    _ensure_tool_choice_allowed(req.tool_choice, provider="openai", settings=settings)
+    tools = _filter_allowed_tools(req.tools or [], provider="openai", settings=settings)
+    return {
+        "provider": "openai",
+        "tools": tools,
+        "tool_choice": req.tool_choice,
+    }
+
+
+def _anthropic_tool_config(
+    req: AnthropicMessagesRequest, *, settings: Settings
+) -> dict[str, Any] | None:
+    if not settings.tool_forward_enabled:
+        return None
+    has_tools = isinstance(req.tools, list) and len(req.tools) > 0
+    has_choice = req.tool_choice is not None
+    if not has_tools and not has_choice:
+        return None
+    _ensure_tool_choice_allowed(req.tool_choice, provider="anthropic", settings=settings)
+    tools = _filter_allowed_tools(req.tools or [], provider="anthropic", settings=settings)
+    return {
+        "provider": "anthropic",
+        "tools": tools,
+        "tool_choice": req.tool_choice,
+    }
+
+
+def _openai_has_tooling_context(req: ChatCompletionsRequest, messages: list[dict[str, Any]]) -> bool:
+    if isinstance(req.tools, list) and len(req.tools) > 0:
+        return True
+    if req.tool_choice is not None:
+        return True
+    for m in messages:
+        role = m.get("role")
+        if role == "tool":
+            return True
+        if role == "assistant" and m.get("tool_calls"):
+            return True
+    return False
+
+
+def _anthropic_content_has_tool_blocks(content: Any) -> bool:
+    if not isinstance(content, list):
+        return False
+    for item in content:
+        if isinstance(item, dict) and item.get("type") in {"tool_use", "tool_result"}:
+            return True
+    return False
+
+
+def _anthropic_has_tooling_context(req: AnthropicMessagesRequest) -> bool:
+    if isinstance(req.tools, list) and len(req.tools) > 0:
+        return True
+    if req.tool_choice is not None:
+        return True
+    if _anthropic_content_has_tool_blocks(req.system):
+        return True
+    for m in req.messages:
+        if _anthropic_content_has_tool_blocks(m.content):
+            return True
+    return False

app/main.py

@@ -35,7 +35,6 @@ from .http.tool_bridge import (
     _allowed_stream_tool_event,
     _allowed_tool_events,
     _anthropic_forced_tool_name,
-    _anthropic_tool_name as _shared_anthropic_tool_name,
     _anthropic_tool_result_block,
     _anthropic_tool_use_block,
     _forced_tool_event_from_text,
@@ -43,9 +42,14 @@ from .http.tool_bridge import (
     _json_string,
     _openai_forced_tool_name,
     _openai_tool_call,
-    _openai_tool_name as _shared_openai_tool_name,
     _tool_code_single_arg_name,
 )
+from .http.tooling_policy import (
+    _anthropic_has_tooling_context,
+    _anthropic_tool_config,
+    _openai_has_tooling_context,
+    _openai_tool_config,
+)
 from .lingma_pool import LingmaPool, PoolInstance
 from .logging_config import configure_logging, get_logger, request_id_var
 from .model_map import build_model_name_map, flatten_model_keys, resolve_model
@@ -379,115 +383,6 @@ def _include_usage(stream_options: dict | None) -> bool:
     return bool(stream_options.get("include_usage"))
 
 
-def _tool_allowlist() -> set[str]:
-    return {name.strip() for name in settings.tool_allowlist if isinstance(name, str) and name.strip()}
-
-
-def _openai_tool_name(tool: Any) -> str | None:
-    return _shared_openai_tool_name(tool)
-
-
-def _anthropic_tool_name(tool: Any) -> str | None:
-    return _shared_anthropic_tool_name(tool)
-
-
-def _filter_allowed_tools(tools: list[dict[str, Any]], *, provider: str) -> list[dict[str, Any]]:
-    allowlist = _tool_allowlist()
-    if not allowlist:
-        return tools
-    name_fn = _openai_tool_name if provider == "openai" else _anthropic_tool_name
-    return [tool for tool in tools if (name := name_fn(tool)) and name in allowlist]
-
-
-def _ensure_tool_choice_allowed(tool_choice: Any, *, provider: str) -> None:
-    allowlist = _tool_allowlist()
-    if not allowlist:
-        return
-    forced_name = (
-        _openai_forced_tool_name(tool_choice)
-        if provider == "openai"
-        else _anthropic_forced_tool_name(tool_choice)
-    )
-    if forced_name and forced_name not in allowlist:
-        raise HTTPException(
-            status_code=400,
-            detail={
-                "error": {
-                    "type": "invalid_request_error",
-                    "message": f"tool '{forced_name}' is not allowed",
-                }
-            },
-        )
-
-
-def _openai_tool_config(req: ChatCompletionsRequest) -> dict[str, Any] | None:
-    if not settings.tool_forward_enabled:
-        return None
-    has_tools = isinstance(req.tools, list) and len(req.tools) > 0
-    has_choice = req.tool_choice is not None
-    if not has_tools and not has_choice:
-        return None
-    _ensure_tool_choice_allowed(req.tool_choice, provider="openai")
-    tools = _filter_allowed_tools(req.tools or [], provider="openai")
-    return {
-        "provider": "openai",
-        "tools": tools,
-        "tool_choice": req.tool_choice,
-    }
-
-
-def _anthropic_tool_config(req: AnthropicMessagesRequest) -> dict[str, Any] | None:
-    if not settings.tool_forward_enabled:
-        return None
-    has_tools = isinstance(req.tools, list) and len(req.tools) > 0
-    has_choice = req.tool_choice is not None
-    if not has_tools and not has_choice:
-        return None
-    _ensure_tool_choice_allowed(req.tool_choice, provider="anthropic")
-    tools = _filter_allowed_tools(req.tools or [], provider="anthropic")
-    return {
-        "provider": "anthropic",
-        "tools": tools,
-        "tool_choice": req.tool_choice,
-    }
-
-
-def _openai_has_tooling_context(req: ChatCompletionsRequest, messages: list[dict[str, Any]]) -> bool:
-    if isinstance(req.tools, list) and len(req.tools) > 0:
-        return True
-    if req.tool_choice is not None:
-        return True
-    for m in messages:
-        role = m.get("role")
-        if role == "tool":
-            return True
-        if role == "assistant" and m.get("tool_calls"):
-            return True
-    return False
-
-
-def _anthropic_content_has_tool_blocks(content: Any) -> bool:
-    if not isinstance(content, list):
-        return False
-    for item in content:
-        if isinstance(item, dict) and item.get("type") in {"tool_use", "tool_result"}:
-            return True
-    return False
-
-
-def _anthropic_has_tooling_context(req: AnthropicMessagesRequest) -> bool:
-    if isinstance(req.tools, list) and len(req.tools) > 0:
-        return True
-    if req.tool_choice is not None:
-        return True
-    if _anthropic_content_has_tool_blocks(req.system):
-        return True
-    for m in req.messages:
-        if _anthropic_content_has_tool_blocks(m.content):
-            return True
-    return False
-
-
 def _resolve_ask_mode(model: str, has_tooling_context: bool) -> str:
     return _shared_resolve_ask_mode(
         model,
@@ -557,7 +452,7 @@ async def v1_chat_completions(req: ChatCompletionsRequest, request: Request):
     #   1. Reuse the upstream sessionId so Lingma/Qwen hits its KV cache.
     #   2. Send only the new user message instead of the whole history.
     #   3. Stick the request to the pool instance that originally served it.
-    tool_config = _openai_tool_config(req)
+    tool_config = _openai_tool_config(req, settings=settings)
     has_tooling_context = _openai_has_tooling_context(req, messages_dump)
     execution = await prepare_execution_context(
         protocol="chat",
@@ -1023,7 +918,7 @@ async def v1_messages(req: AnthropicMessagesRequest, request: Request):
 
     # ------------------------------------------------------------- session reuse
     try:
-        tool_config = _anthropic_tool_config(req)
+        tool_config = _anthropic_tool_config(req, settings=settings)
     except HTTPException as exc:
         detail = exc.detail if isinstance(exc.detail, dict) else {}
         error = detail.get("error") if isinstance(detail.get("error"), dict) else {}