copilotkit

web-chat/copilotkit

完整的 AG-UI + CopilotKit 前端 example，演示 agent-adaptor 的四条纵向通路：

1. Streaming：文本、thinking、tool_call 通过一条 stream.Events() 通道流式传递，终局由一次 stream.Result() 收口。若 Driver 没有发布 assistant delta 但终局 Result.Text 非空，后端会在 terminal 前投影一次完整 assistant message；已有流式文本时绝不重复。
2. HITL：没有安装 OnApproval 回调时，approval 以自带 responder 的 *adaptor.ApprovalRequest 事件出现在同一条流上。宿主停放请求后直接调用 req.Approve(ctx) / req.Deny(ctx, reason) / req.Answer(ctx, option)；ErrApprovalResolved 映射 HTTP 410，ErrApprovalKindMismatch 映射 400。NoticeApprovalResolved 会自动清掉 pending。
3. Recovery：每个浏览器有稳定 thread_id，右侧面板通过 /session/events + /decision/pending 恢复历史与未决决策。EventMeta.Sequence 只在单次 run 内排序；跨 run 重放使用 hosttools/sessionrecorder 分配的 HostSeq。
4. User-prompt persistence：user prompt 不会自动进入 SDK 持久层（thread store 只存 resume 元数据；driver 只 emit assistant 侧）。handleAgent 用 userTurnEvents(lastUserMessageID(input), prompt) 构造三段 adaptor.TextDelta{Role: RoleUser, Phase: Start/Content/End}，让它经过和 driver 事件相同的 fan-out。刷新页面拉 /session/events 即可恢复含 user 气泡的完整 transcript。
   实现入口：server.go::handleAgent + agui_run_session.go::recordUserTurn；验证用例：agui_run_session_test.go::TestAGUIRunSessionRecordsUserTurnBeforeAssistant。

后端只调用真实本机 CLI：

Quick Start

./examples/web-chat/copilotkit/start-all.sh codex
./examples/web-chat/copilotkit/start-all.sh claude
./examples/web-chat/copilotkit/start-all.sh cursor

打开 http://localhost:3000 。Go backend 和 Next.js dev server 默认都只绑定 127.0.0.1；这个示例会调用已登录的真实 CLI，不会默认暴露到局域网。

团队委托 showcase 复用同一套前端，但由它自己的脚本启动正确的 Go backend 并切换为团队工作流页面（不显示该 backend 不提供的 HITL 恢复侧栏）：

./examples/showcases/team-agent-workflow/start-all.sh claude

cursor 在没有正式 assistant delta 协议时不会伪造 token 流；后端只把 Driver 已确认的最终 Result.Text 恰好投影一次，并同步写入恢复历史。

也可以只起后端：

./examples/web-chat/copilotkit/start.sh claude

架构

Browser
  ├─ <CopilotChat/>  (React, @copilotkit/react-ui)
  │     │  POST /api/copilotkit
  │     ▼
  │  Next.js CopilotRuntime + HttpAgent
  │     │  POST /agent  (AG-UI RunAgentInput)
  │     ▼
  │  Go backend
  │     ├─ ai.Thread(key).Stream(ctx, prompt)   →  adaptor.Stream
  │     └─ for ev := range stream.Events()      →  一条通道，两个去处
  │            ├─ recorder.Record(...)                    (历史，HostSeq 游标)
  │            ├─ translator.Translate(ev)  →  SSE        (实时)
  │            └─ *adaptor.ApprovalRequest  →  pending store (自带 responder)
  │        stream.Result()  →  Result.Text fallback（仅无 assistant delta）
  │                         →  translator.CloseResult(...) (终局判决)
  │
  └─ 直接 fetch (旁路) —— 用于 HITL & 恢复
         GET  /session/events?thread_id=T&after=N
         GET  /decision/pending?thread_id=T
         POST /decision/resolve

前置条件

• Go 1.26.5+
• Node.js 20+ + npm
• 选用的 codex / claude / cursor CLI 已安装、已登录，并且 --help 可运行

前端依赖固定使用 CopilotKit 1.63.2 与 next@16.3.0-preview.8。选择该 Next preview 是因为截至冻结日最新 stable 16.2.12 仍落在已公开的 high advisory 范围内；同时以局部 overrides 将 Hono、PostCSS、fast-uri 提升到 兼容的安全补丁版本，并更新 MCP SDK、DOMPurify、Mermaid 等仍在兼容范围内的 传递依赖。lockfile 只保存 npm 官方 registry URL，CI 会执行 fresh npm ci、 lint、build 与 npm audit --omit=dev --audit-level=high。冻结时 production tree 没有 high/critical；剩余 moderate/low 来自 CopilotKit Runtime 尚未接受的 @hono/node-server/uuid major 以及暂无已发布修复的上游链路，因此没有用 npm audit fix --force 或不兼容的全局 override 掩盖风险。

后端 HTTP 端点

环境变量

前端：

如需从其他机器访问，必须显式设置监听地址与准确 Origin，例如 ADDR=0.0.0.0:8080 CORS_ORIGIN=https://chat.example.com；不要在不受信网络中使用 CORS_ORIGIN=*，因为每个请求都可能触发真实模型调用。

Visual subagent delegation hook

The backend can render remote A2A delegation progress in the same CopilotKit AG-UI stream. Create an a2adelegation.Service from the remote Agent Cards and pass team.Option() to adaptor.New (or pass the service through adaptor.WithRunServices(team)). The service creates an authenticated, run-scoped delegate_to_agent MCP sidecar, exposes it through the typed MCP contract, binds its cleanup to the run, and folds progress into the Agent's single event stream as adaptor.SubagentUpdate. The AG-UI bridge projects those updates into one incrementally patched AG-UI Activity message per delegation (activityType="subagent", messageId=delegationId); Claude/Codex/Cursor receives only the final structured MCP result. In team-workflow mode the CopilotKit frontend renders these Activity messages as live cards in the right sidebar. A role's human-facing name carries its provider base, so the card tag shows Claude Code, Codex, Cursor, or CodeBuddy instead of the common A2A transport. Structured plan output shaped as a file value is rendered as a previewable and downloadable PLAN.md attachment.

This example's default main path starts one local parent CLI. Hosts that enable delegation should run an A2A bridge for each remote agent (see examples/a2a-server and docs/a2a.md), construct the service once, keep it alive for the equipped Agent, and close it during host shutdown. No stringly runtime metadata or bridge-specific run handle is involved.

The important boundary for UI authors: render activityType="subagent" as a nested visual group, but do not turn it into a parent assistant message. The Activity content may include parentToolCallId when the host can correlate the delegation sidecar with a parent provider tool-use ID, but UI code should not require it. subagentId is the stable nested group key and runId is its run scope. The parent transcript should contain the normal tool call plus the concise final delegation result only.

相关文档

• docs/streaming.md
• docs/run-policy.md
• docs/streaming-adapter-contract.md