接口联调
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# 多智能体圆桌 · Step 1 · 任务理解智能体接口与实现
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> Step 1(`/page/roundtable/planning` 的"任务意图与澄清"页)对应 `RoundtablePlanningPage.tsx` 里 `currentStep === 1` 的渲染分支。当前它是纯前端 mock —— 用户发消息后 `setTimeout(1500)` 拼一段固定话术回。本文档定义一个**内置任务理解智能体 + 2 个轻量接口**,让 step 1 跑起来真正的对话,为 step 2 输入更高质量的"任务目标 + 约束"。
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>
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> 整体风格直接参照 `multi-agent-api.md` / `multi-agent-backend-dev.md`。
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---
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## 1. 目标与边界
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### ✅ 要做的事
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- 内置一个智能体:**任务理解智能体**(`roundtable-intent`),跟 6 个 roundtable 席位同等地位
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- 提供 2 个接口:`/api/intent/init` 和 `/api/intent/stream`
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- 复用 step 2 的 SSE 协议风格(前端只需 1 个新 helper)
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- 让用户跟智能体多轮澄清后,把最终"目标 + 约束"传给 step 2 的 `runOrchestration`
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### ❌ 不做的事
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- 不重新设计澄清协议(直接用 `ask_clarification` 工具 + ClarificationMiddleware 现成机制,跟 step 2 leader 一样)
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- 不做"自动跳过"按钮的真实业务逻辑(保留前端按钮形态即可)
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- 不做时间线(timelineEntries)的后端持久化(前端临时状态够用)
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- 不做"评分/置信度"等假指标
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- 不做单独的"任务理解专员模型选择"——直接用全局 `DEFAULT_MODEL`
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---
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## 2. 数据流概览
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```
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[Step 1 入口]
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↓
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前端:POST /api/intent/init
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← {agent_id: "roundtable-intent", thread_id: "..."}
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用户输入第一句话:"帮我规划一个生产系统安全改造方案"
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↓
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前端:POST /api/intent/stream (SSE)
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← (流式 AI 文本) "好的,预算大致是多少?"
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← {status: "asking", content: "..."} ← 智能体反问中,需要用户继续
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用户回:"500 万左右"
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↓
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前端再次 POST /api/intent/stream
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← (流式) "明白,还有什么时间约束吗?"
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← {status: "asking", ...}
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...对话进行几轮 ...
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用户:可以了
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↓
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前端再 POST /api/intent/stream
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← (流式) "好,我理解的任务是: <汇总>"
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← {status: "done", content: "<最终汇总文本>", summary: {...}} ← 信息充分,可进入 step 2
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[Step 1 完成 → Step 2 init]
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前端把 summary.objective + summary.constraints 拼成 step 2 的 buildInitialIntent()
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```
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---
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## 3. 接口设计
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跟 step 2 完全同构。`/api/intent/init` 简化版(只建 1 个 thread + 1 个 agent,没有"协调"概念);`/api/intent/stream` 跟 `/api/multi-agent/run/stream` 的 special 分支几乎一样。
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### 3.1 `POST /api/intent/init`
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**请求体**
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```json
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{
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"model": "deepseek-chat" // 可选,默认全局 DEFAULT_MODEL
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}
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```
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**响应 200**
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```json
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{
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"status": "success",
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"agent_id": "roundtable-intent",
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"thread_id": "<langgraph_thread_id>"
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}
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```
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**行为**:
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1. 鉴权(透传 `Authorization`)
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2. 调上游 `POST /api/threads` 建 1 个 thread
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3. 直接返回 `agent_id = "roundtable-intent"`(**这是内置 agent,不需要每次新建**)
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**与 step 2 `/init` 的区别**:
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- 没有"协调智能体"概念,只有 1 个 agent
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- 没有 6 个 sub 席位,只有 1 个 thread
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- 不需要传 `agent_names` 数组
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- `agent_id` 是固定字符串 `"roundtable-intent"`,不带 timestamp 后缀(智能体本身是内置、长期、复用的)
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### 3.2 `POST /api/intent/stream`
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**请求体**
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```json
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{
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"thread_id": "<from /init>",
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"message": "用户这一轮要说的话",
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"model": "deepseek-chat" // 可选
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}
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```
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**响应**:`text/event-stream`,SSE 流式。
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**SSE 帧组成**:
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1. 透传上游 LangGraph 的所有帧(`event: metadata` / `event: messages` / `event: values`)—— 前端用现有的 `extractAiTextDelta` 解析 AI 文本增量
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2. 流末追加一个**状态帧**(跟 step 2 同样模式):
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```json
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{
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"status": "asking" | "done" | "error",
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"content": "<本轮 AI 文本>",
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"summary": {
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"objective": "...", // 仅 status=done 时有: 任务目标
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"constraints": ["...", ...], // 仅 status=done 时有: 约束清单
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"assumptions": ["...", ...] // 仅 status=done 时有: 关键假设
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}
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}
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```
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**`status` 取值**:
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- `"asking"` —— 智能体还在追问,前端应该把焦点放回输入框
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- `"done"` —— 智能体宣布"信息已充分",前端就可以亮起"进入下一步"按钮,并拿 `summary` 拼 step 2 的初始 intent
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- `"error"` —— 上游异常,`content` 里是错误信息
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**判定 done/asking 的简单策略**(后端实现):
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- 智能体在 SOUL 里被告知:信息已充分时**必须**调 `present_intent_summary` 工具(或直接在 AIMessage 里用一个固定标记 `[INTENT_READY]`),后端识别后发 `done` 帧
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- 否则一律是 `asking`
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> 上面"summary 工具"是新增的内置工具吗?不一定。最省事的做法是**让模型用 JSON 块输出**,后端用正则提取:
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>
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> ```
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> [INTENT_READY]
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> ```json
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> {"objective": "...", "constraints": ["..."], "assumptions": ["..."]}
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> ```
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> ```
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>
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> 后端流末扫一下最末 AIMessage 里有没有这个标记,有就 parse JSON 出来填到 summary,发 `done`;没有就发 `asking`。
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---
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## 4. 内置智能体配置
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**位置**:`offline-backend-20260512/backend/.deer-flow/agents/roundtable-intent/`
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### 4.1 `config.yaml`
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```yaml
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id: roundtable-intent
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name: 任务理解智能体
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description: 帮助用户明确任务目标、约束、关键假设,为后续多智能体圆桌研讨准备结构化输入。
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```
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### 4.2 `SOUL.md`
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```markdown
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# 任务理解智能体
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## 角色定位
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你是多智能体圆桌研讨的"任务理解专员"。你的工作是在用户和 6 个圆桌席位之间架一座桥:
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通过 2-5 轮简短追问,把用户模糊的需求转化成结构化的「任务目标 + 约束 + 关键假设」。
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## 核心职责
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- 用清晰、简短的问题引导用户补全关键信息(优先级: 目标 > 硬约束 > 软偏好)
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- 不要追问已经清楚的事
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- 不要做方案,不要给具体技术建议——那是后面 6 个席位的工作
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- 信息足够后,立即停止追问,产出结构化汇总
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## 信息充分性判定
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当满足以下条件时,认为信息已充分:
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1. 明确的任务目标(至少能写出一句 "用户希望实现 X")
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2. 至少 1 条硬约束(预算/时间/合规/范围之一)
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3. 没有明显的歧义点
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## 信息汇总产出
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信息充分时,你必须在回复末尾输出**精确的标记 + JSON 块**(给后端识别用):
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```
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[INTENT_READY]
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```json
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{
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"objective": "用一句话写出用户最终要做的事",
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"constraints": ["预算 ≤ XXX 万", "时间 ≤ XXX 天", ...],
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"assumptions": ["假设 1", "假设 2", ...]
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}
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```
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```
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输出前可以先用自然语言总结一遍给用户看(让用户能 review 内容),再附上述标记 + JSON。
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## 输出风格
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- 一次回复不超过 3 句话
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- 提问要具体,不要"还有什么补充吗"这种空问
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- 用 emoji 简短点缀(❓ 表示问题, ✅ 表示明确, 📋 表示汇总)
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## 边界
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- 不调用 agent_orchestration(这是 step 2 的协调智能体的事)
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- 不写文件、不做计算、不联网
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- 用户消息歧义大时,优先调 ask_clarification 工具引导
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```
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### 4.3 注册方式
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跟现有 6 个 `roundtable-*` 一样,通过 `_sync_legacy_agents()`(`app/gateway/routers/agents.py`)在下次任意 `/api/agents` 请求时自动 upsert 进 `agents` 表,`user_id IS NULL` 标记为内置。**零代码改动**。
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---
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## 5. 后端实现要点
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### 5.1 新建 router 文件
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**位置**:`offline-backend-20260512/backend/app/gateway/routers/intent.py`
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```python
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"""任务理解智能体接口 - Step 1 的极简包装。
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跟 multi_agent.py 同构但简化:
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- 没有 broadcast(单 thread,无需广播)
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- 没有派活逻辑
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- 没有 leader/special 分支,只有一种调用方式
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- 流末状态帧解析 [INTENT_READY] 标记决定 status=done/asking
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"""
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from fastapi import APIRouter, Body, HTTPException, Request
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from fastapi.responses import StreamingResponse
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import httpx, json, re, asyncio, logging
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logger = logging.getLogger(__name__)
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router = APIRouter(prefix="/api/intent", tags=["intent"])
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# 复用 multi_agent.py 里已有的工具函数
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from app.gateway.routers.multi_agent import (
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_loopback_base, _auth_headers,
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_create_thread, _stream_upstream, _parse_last_messages,
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_flatten_content, _run_payload,
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)
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INTENT_AGENT_ID = "roundtable-intent"
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_INTENT_READY_PATTERN = re.compile(
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r"\[INTENT_READY\]\s*```json\s*(\{.*?\})\s*```",
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re.DOTALL,
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)
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@router.post("/init")
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async def init_intent(request: Request, payload: dict = Body(...)) -> dict:
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base = _loopback_base(request)
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headers = _auth_headers(request)
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async with httpx.AsyncClient(timeout=None) as client:
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thread_id = await _create_thread(client, base, headers)
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return {
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"status": "success",
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"agent_id": INTENT_AGENT_ID,
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"thread_id": thread_id,
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}
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@router.post("/stream")
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async def stream_intent(request: Request, payload: dict = Body(...)) -> StreamingResponse:
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thread_id = str(payload.get("thread_id") or "").strip()
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message = str(payload.get("message") or "").strip()
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model_name = str(payload.get("model") or "deepseek-chat")
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if not thread_id or not message:
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raise HTTPException(status_code=400, detail="thread_id and message required")
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base = _loopback_base(request)
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headers = _auth_headers(request)
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async def gen():
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async with httpx.AsyncClient(timeout=None) as client:
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try:
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body = _run_payload(
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agent_name=INTENT_AGENT_ID,
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model_name=model_name,
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thread_id=thread_id,
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new_message=message,
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excluded_tools=["web_search", "present_files",
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"view_image", "agent_orchestration"],
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skill_stop_names=[],
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)
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captured = []
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async for line, done in _stream_upstream(client, base, headers, thread_id, body):
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if line is not None:
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yield (line if line.endswith("\n") else line + "\n")
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elif done is not None:
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captured = done
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messages = _parse_last_messages(captured)
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last_ai = {}
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for m in reversed(messages):
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if isinstance(m, dict) and (m.get("type") or "").lower() in ("ai", "aimessage", "aimessagechunk"):
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last_ai = m
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break
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content = _flatten_content(last_ai.get("content", ""))
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# 检测 [INTENT_READY] 标记
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match = _INTENT_READY_PATTERN.search(content)
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if match:
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try:
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summary = json.loads(match.group(1))
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except json.JSONDecodeError:
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summary = None
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frame = {"status": "done", "content": content, "summary": summary}
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else:
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frame = {"status": "asking", "content": content}
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yield f"data: {json.dumps(frame, ensure_ascii=False)}\n\n"
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except HTTPException as exc:
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yield f"data: {json.dumps({'status':'error','content':f'[{exc.status_code}] {exc.detail}'}, ensure_ascii=False)}\n\n"
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except Exception as exc:
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logger.exception("intent stream failure")
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yield f"data: {json.dumps({'status':'error','content':f'unexpected: {exc!r}'}, ensure_ascii=False)}\n\n"
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return StreamingResponse(
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gen(),
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media_type="text/event-stream",
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headers={"Cache-Control": "no-cache", "X-Accel-Buffering": "no", "Connection": "keep-alive"},
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)
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```
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### 5.2 在 `app/gateway/app.py` 注册
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```python
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from app.gateway.routers import intent
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app.include_router(intent.router)
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```
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---
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## 6. 前端实现要点
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### 6.1 新增 API helper
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**位置**:`frontend-web/src/roundtable-planning/api/intent.ts`
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```ts
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import { apiFetch } from "@/core/api/fetch-client";
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import { getBackendBaseURL } from "@/core/config";
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export interface IntentInitResponse {
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status: "success";
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agent_id: string;
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thread_id: string;
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}
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export async function initIntent(model?: string): Promise<IntentInitResponse> {
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const res = await apiFetch(`${getBackendBaseURL()}/api/intent/init`, {
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method: "POST",
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headers: { "Content-Type": "application/json" },
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body: JSON.stringify({ model }),
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});
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if (!res.ok) throw new Error(`init intent failed (${res.status}): ${await res.text()}`);
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return res.json();
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}
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export interface IntentSummary {
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objective: string;
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constraints: string[];
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assumptions?: string[];
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}
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export interface StreamIntentRequest {
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threadId: string;
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message: string;
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model?: string;
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signal?: AbortSignal;
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onTextDelta?: (text: string, id: string) => void;
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}
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export interface StreamIntentResult {
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status: "asking" | "done" | "error";
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content: string;
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summary: IntentSummary | null;
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}
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export async function streamIntent(req: StreamIntentRequest): Promise<StreamIntentResult> {
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// 实现:reader 循环跟 streamMultiAgent 几乎一样,只是状态帧解析改成
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// {status, content, summary?} 格式。
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// ...(参考 multi-agent.ts 的 streamMultiAgent 改写,简化 80%)
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}
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```
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### 6.2 改造 `RoundtablePlanningPage.tsx` 的 step1 渲染
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替换 `handleSendMessage`:
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```ts
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const [intentThreadId, setIntentThreadId] = useState<string | null>(null);
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const [intentReady, setIntentReady] = useState<IntentSummary | null>(null);
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useEffect(() => {
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if (currentStep === 1 && !intentThreadId) {
|
||||
initIntent(DEFAULT_MODEL).then(r => setIntentThreadId(r.thread_id));
|
||||
}
|
||||
}, [currentStep]);
|
||||
|
||||
const handleSendMessage = async () => {
|
||||
if (!inputText.trim() || !intentThreadId) return;
|
||||
const userText = inputText.trim();
|
||||
// (push user msg to interactiveMessages 略)
|
||||
setInputText("");
|
||||
|
||||
// 占位 agent 气泡
|
||||
const agentMsgId = pushAgentPlaceholder("任务理解智能体");
|
||||
|
||||
const res = await streamIntent({
|
||||
threadId: intentThreadId,
|
||||
message: userText,
|
||||
model: DEFAULT_MODEL,
|
||||
onTextDelta: (delta) => appendToAgentMsg(agentMsgId, delta),
|
||||
});
|
||||
|
||||
finalizeAgentMsg(agentMsgId, res.content);
|
||||
if (res.status === "done" && res.summary) {
|
||||
setIntentReady(res.summary);
|
||||
triggerToast("✅ 任务理解完成,可以进入圆桌研讨");
|
||||
}
|
||||
};
|
||||
```
|
||||
|
||||
### 6.3 "进入 step 2"按钮的联动
|
||||
|
||||
- 当前页面已有"完成澄清/进入下一步"按钮(应该是路由到 `currentStep === 2`)
|
||||
- 改造:只有 `intentReady !== null` 时该按钮才 enabled
|
||||
- 点击后:把 `intentReady.objective + intentReady.constraints` 写入 `buildInitialIntent()` 的源(替换现在按 `interactiveMessages` 找最后一条 user msg + budgetLimit 拼接的逻辑)
|
||||
|
||||
```ts
|
||||
const buildInitialIntent = useCallback(() => {
|
||||
if (intentReady) {
|
||||
return `${intentReady.objective}\n\n约束条件:\n${intentReady.constraints.map(c => `- ${c}`).join("\n")}\n\n请基于上述目标与约束,在圆桌内调度合适的子智能体完成研讨。`;
|
||||
}
|
||||
// fallback: 旧逻辑保留兜底
|
||||
const lastUserMessage = [...interactiveMessages].reverse().find(m => m.sender === "user");
|
||||
const userIntent = lastUserMessage?.content ?? "请围绕给定任务展开圆桌研讨";
|
||||
const constraints = `预算硬约束:${budgetLimit} 万元`;
|
||||
return `${userIntent}\n\n约束条件:${constraints}\n\n请基于上述目标与约束,在圆桌内调度合适的子智能体完成研讨。`;
|
||||
}, [interactiveMessages, budgetLimit, intentReady]);
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## 7. 实施清单
|
||||
|
||||
| 优先级 | 项 | 文件 |
|
||||
|---|---|---|
|
||||
| P0 | 内置 agent 目录 | `backend/.deer-flow/agents/roundtable-intent/{config.yaml,SOUL.md}` |
|
||||
| P0 | 新 router | `backend/app/gateway/routers/intent.py` |
|
||||
| P0 | 注册 router | `backend/app/gateway/app.py`(一行 `include_router`) |
|
||||
| P0 | 前端 helper | `frontend-web/src/roundtable-planning/api/intent.ts` |
|
||||
| P0 | 前端页面改造 | `frontend-web/src/roundtable-planning/pages/RoundtablePlanningPage.tsx`(handleSendMessage + buildInitialIntent + 入口 useEffect) |
|
||||
| P1 | step 1 进入下一步按钮 disabled 状态联动 `intentReady` | 同上 |
|
||||
| P2 | 单测 | `backend/tests/test_intent.py`(init 返回 agent_id 固定值, stream 识别 INTENT_READY 标记) |
|
||||
| P3 | 失败兜底(INTENT_READY 标记被模型遗漏时的"用户手动确认进入下一步"按钮) | 前端 |
|
||||
|
||||
---
|
||||
|
||||
## 8. 与 step 2 的衔接
|
||||
|
||||
```
|
||||
step 1 输出: intentReady.objective + intentReady.constraints
|
||||
↓
|
||||
step 2 入口: buildInitialIntent() 拼成 leader 的 new_message
|
||||
↓
|
||||
step 2 leader 不再需要主动反问澄清(因为 step1 已经清完了),
|
||||
除非模型遇到完全意料之外的歧义
|
||||
↓
|
||||
研讨更聚焦,减少 step2 阶段的 clarification 轮次
|
||||
```
|
||||
|
||||
副产物:协调智能体的 SOUL 可以稍微调整(参考 `multi_agent.py:soul = "#核心定位..."` 那段),加一句"用户已经经过任务理解智能体澄清,task 描述里包含目标+约束,请直接开始派活而不是再反问",进一步减少 step2 的反问。
|
||||
|
||||
---
|
||||
|
||||
## 9. 路径速查
|
||||
|
||||
| 资源 | 位置 |
|
||||
|---|---|
|
||||
| Step 1 渲染 | `RoundtablePlanningPage.tsx` 内 `currentStep === 1` 分支(约 line 1418+) |
|
||||
| 新增前端 helper | `frontend-web/src/roundtable-planning/api/intent.ts` |
|
||||
| 新增后端 router | `offline-backend-20260512/backend/app/gateway/routers/intent.py` |
|
||||
| 内置 agent | `offline-backend-20260512/backend/.deer-flow/agents/roundtable-intent/` |
|
||||
| 路由注册 | `offline-backend-20260512/backend/app/gateway/app.py` |
|
||||
| 参照实现 | `multi_agent.py`(接口模式、SSE 包装、状态帧) |
|
||||
|
||||
---
|
||||
|
||||
## 10. 验收清单
|
||||
|
||||
- [ ] 进入 step 1 自动调 `/api/intent/init`,拿到 thread_id
|
||||
- [ ] 用户每次发消息后,任务理解智能体真实流式输出(不是 setTimeout)
|
||||
- [ ] 智能体能在 2-5 轮对话后自动停止追问,发 `status: done` 帧并附 summary
|
||||
- [ ] step 2 的初始 intent 用 step1 的 summary 拼接,不再依赖 `budgetLimit` 这种页面状态
|
||||
- [ ] 离开/重新进入 step 1 时,thread_id 状态干净(不会带着上次的对话)
|
||||
- [ ] 任何接口失败都不让 step 1 卡死(容错的"用旧 mock 兜底"或者明确错误提示)
|
||||
Reference in new issue
Block a user