fix: show tool parameters and skip duplicate calls

backend/wisegrade/chat_api.py

@@ -1,6 +1,5 @@
 """Persistent teacher conversations and SSE agent orchestration."""
 import json
-import re
 import time
 from concurrent.futures import ThreadPoolExecutor
 from datetime import timedelta
@@ -9,13 +8,13 @@ from uuid import UUID
 
 from fastapi import APIRouter, Depends, HTTPException
 from fastapi.responses import StreamingResponse
-from pydantic import BaseModel, Field
+from pydantic import BaseModel, Field, ValidationError
 from sqlalchemy import delete, select
 from sqlalchemy.exc import IntegrityError
 from sqlalchemy.orm import Session, sessionmaker
 
 from .actions import action_dict, confirm, prepare, require_scope
-from .agent_tools import execute, tool_specs
+from .agent_tools import TOOLS, execute, tool_specs
 from .config import get_settings
 from .db import get_db
 from .llm import ModelError
@@ -31,7 +30,8 @@ SYSTEM = """你是 WiseGrade 教师助手。仅使用提供的工具查询或准
 课程与评分规则以结构化数据库为准；指定批次时必须使用其快照。名称或版本有歧义时请先列出候选并请教师澄清。
 报告内容只能根据检索证据回答，引用资料名、页码或幻灯片编号和原文；无证据时说明未找到。
 不要把未完成、失败或无法评分算零分或完整成绩。教师复核分数必须由教师当前消息明确给出。
-所有写入操作仅能准备确认卡片，绝不能声称已经执行。确认由教师点击界面按钮完成。不要要求模型调用确认工具。"""
+所有写入操作仅能准备确认卡片，绝不能声称已经执行。确认由教师点击界面按钮完成。不要要求模型调用确认工具。
+同一轮已取得工具结果后不要以相同参数重复调用；分页查询须使用结果中的 next offset。"""
 
 
 class CreateConversation(BaseModel):
@@ -165,27 +165,39 @@ def _event(name, payload):
 
 
 def _safe_arguments(arguments):
-    """Keep useful identifiers without persisting secrets or large teacher/student text."""
+    """Record bounded tool inputs needed to explain a call, while omitting review prose."""
     if not isinstance(arguments, dict):
         return {}
-    allowed = {"course_version_id", "batch_id", "project_id", "score_id", "task_id",
-               "criterion_id", "format", "status", "offset", "limit"}
+    numeric = {"course_version_id", "batch_id", "project_id", "score_id", "task_id",
+               "rubric_version_id", "score", "offset", "limit", "project_offset", "criterion_offset"}
+    text_limits = {"query": 300, "criterion_id": 100, "format": 20, "status": 30,
+                   "student_no": 50, "relative_dir": 500}
     result = {}
     for key, value in arguments.items():
-        if key not in allowed:
-            continue
-        if isinstance(value, (int, float)) and not isinstance(value, bool):
+        if key in numeric and isinstance(value, (int, float)) and not isinstance(value, bool):
             result[key] = value
-        elif isinstance(value, str) and re.fullmatch(r"[A-Za-z0-9_.-]{1,80}", value):
-            result[key] = value
-        else:
+        elif key in text_limits and isinstance(value, str):
+            result[key] = value[:text_limits[key]]
+        elif key in {"comment", "reason"}:
             result[key] = "[文本已省略]"
-    omitted = sum(key not in result for key in arguments)
+    omitted = sum(key not in result for key in arguments if key not in {"comment", "reason"})
     if omitted:
-        result["omitted_text_fields"] = omitted
+        result["omitted_fields"] = omitted
     return result
 
 
+def _tool_key(name, arguments):
+    """Use validated defaults so omitted and explicit pagination defaults match."""
+    tool = TOOLS.get(name)
+    if not tool:
+        return None
+    try:
+        normalized = tool.schema.model_validate(arguments).model_dump(mode="json", exclude_none=True)
+    except ValidationError:
+        return None
+    return json.dumps([name, normalized], sort_keys=True, ensure_ascii=False)
+
+
 def _result_summary(result):
     if not isinstance(result, dict):
         return "工具已返回结果"
@@ -291,6 +303,7 @@ def _run_agent(factory, conversation_id, run_id, user_text):
         run = db.get(AgentRun, run_id)
         citations = []
         used = []
+        successful_calls = {}
         try:
             client = client_for_chat(db)
             if hasattr(client, "verify_tool_support"):
@@ -336,24 +349,49 @@ def _run_agent(factory, conversation_id, run_id, user_text):
                     call_id = call.get("id") or f"run-{run.id}-call-{ordinal}"
                     entry = {"id": f"{run.id}:{ordinal}:{call_id}", "name": name[:100],
                              "status": "running", "arguments": {}}
-                    used.append(entry)
-                    run.tool_calls = list(used)
-                    yield _record(db, run, "tool", entry)
                     try:
                         arguments = json.loads(call.get("function", {}).get("arguments", "{}"))
                         if not isinstance(arguments, dict):
                             raise ValueError("工具参数须为对象")
-                        entry = {**entry, "arguments": _safe_arguments(arguments)}
-                        result = execute(db, conversation, name, arguments, user_text)
-                        if isinstance(result, dict):
-                            citations.extend(result.get("citations", []))
-                        output = json.dumps(result, ensure_ascii=False, default=str)
-                        if len(output) > 12000:
-                            output = json.dumps({"notice": "结果已按结构压缩；可使用工具分页参数继续查询",
-                                                 **_safe_result(result, name)}, ensure_ascii=False, default=str)
-                        messages.append({"role": "tool", "tool_call_id": call_id, "content": output})
-                        entry = {**entry, "status": "completed", "summary": _result_summary(result),
-                                 "result": _safe_result(result, name)}
+                        visible_arguments = arguments
+                        if name in TOOLS:
+                            try:
+                                visible_arguments = TOOLS[name].schema.model_validate(arguments).model_dump(exclude_none=True)
+                            except ValidationError:
+                                pass
+                        entry["arguments"] = _safe_arguments(visible_arguments)
+                        parse_error = None
+                    except (TypeError, ValueError) as exc:
+                        arguments = {}
+                        parse_error = exc
+                    used.append(entry)
+                    run.tool_calls = list(used)
+                    yield _record(db, run, "tool", entry)
+                    try:
+                        if parse_error:
+                            raise parse_error
+                        key = _tool_key(name, arguments)
+                        previous = successful_calls.get(key) if key else None
+                        if previous:
+                            notice = {"notice": "同一轮已用相同参数调用此工具，请使用先前结果",
+                                      "previous_call_id": previous["tool_call_id"]}
+                            messages.append({"role": "tool", "tool_call_id": call_id,
+                                             "content": json.dumps(notice, ensure_ascii=False)})
+                            entry = {**entry, "status": "skipped", "summary": "重复调用已跳过",
+                                     "result": {"previous_call_id": previous["entry_id"]}}
+                        else:
+                            result = execute(db, conversation, name, arguments, user_text)
+                            if isinstance(result, dict):
+                                citations.extend(result.get("citations", []))
+                            output = json.dumps(result, ensure_ascii=False, default=str)
+                            if len(output) > 12000:
+                                output = json.dumps({"notice": "结果已按结构压缩；可使用工具分页参数继续查询",
+                                                     **_safe_result(result, name)}, ensure_ascii=False, default=str)
+                            messages.append({"role": "tool", "tool_call_id": call_id, "content": output})
+                            entry = {**entry, "status": "completed", "summary": _result_summary(result),
+                                     "result": _safe_result(result, name)}
+                            if key:
+                                successful_calls[key] = {"entry_id": entry["id"], "tool_call_id": call_id}
                     except Exception as exc:
                         # Tool errors are model-visible, but do not grant broader access or leak provider responses.
                         db.rollback()