实现 AI Core 与 Agent Core 基础功能

- 更新 README 描述从后端壳子到 AI Core/Agent Core
- 添加 ToolCall 和 ToolResult 数据结构定义
- 扩展 AgentRun 模型增加输出、错误码、工具调用结果等字段
- 添加 mock 提供商类型支持
- 实现聊天、代理运行、工具调用和提供商管理的核心路由逻辑
- 集成容器化依赖注入和错误处理机制
- 更新 API 接口契约和文档说明

backend/tests/test_agent_core.py

@@ -0,0 +1,181 @@
+import asyncio
+
+from app.agent.permissions import PermissionMode
+from app.agent.tools import ToolExecutionContext
+from app.container import build_container
+from app.contracts import (
+    AgentEventType,
+    AgentRunCreateRequest,
+    AgentRunStatus,
+    ToolCall,
+)
+
+
+def run(coroutine):
+    return asyncio.run(coroutine)
+
+
+def test_mock_provider_completes_agent_run() -> None:
+    async def scenario() -> None:
+        container = build_container()
+        created = await container.agent.create_run(
+            AgentRunCreateRequest(
+                input="hello",
+                provider_id="mock",
+                model="mock-1",
+            )
+        )
+
+        completed = await container.agent.wait(created.run_id)
+        events = [event async for event in container.agent.events(created.run_id)]
+
+        assert completed.status == AgentRunStatus.completed
+        assert completed.output == "Mock response: hello"
+        assert events[0].event == AgentEventType.run_started
+        assert events[-1].event == AgentEventType.run_completed
+
+    run(scenario())
+
+
+def test_agent_calls_registered_tool_and_records_result() -> None:
+    async def scenario() -> None:
+        container = build_container()
+        created = await container.agent.create_run(
+            AgentRunCreateRequest(
+                input='/tool system.echo {"text":"hello tool"}',
+                provider_id="mock",
+                model="mock-1",
+                allowed_tools=["system.echo"],
+            )
+        )
+
+        completed = await container.agent.wait(created.run_id)
+
+        assert completed.status == AgentRunStatus.completed
+        assert completed.current_step == 2
+        assert completed.tool_results[0].success is True
+        assert completed.tool_results[0].output == {"text": "hello tool"}
+        assert completed.output is not None
+        assert "Tool result received" in completed.output
+
+    run(scenario())
+
+
+def test_tool_arguments_are_validated() -> None:
+    async def scenario() -> None:
+        container = build_container()
+        result = await container.tools.execute(
+            ToolCall(
+                tool_call_id="call_invalid",
+                name="math.add",
+                arguments={"left": 1},
+            ),
+            ToolExecutionContext(run_id="run_test"),
+        )
+
+        assert result.success is False
+        assert result.error_code == "TOOL_ARGUMENT_INVALID"
+
+    run(scenario())
+
+
+def test_permission_confirmation_resumes_agent() -> None:
+    async def scenario() -> None:
+        container = build_container()
+        protected_tool = container.tools.get("system.echo")
+        protected_tool.definition.permission = "notes.write"
+        container.permissions.policy.set_rule("notes.write", PermissionMode.confirm)
+
+        created = await container.agent.create_run(
+            AgentRunCreateRequest(
+                input='/tool system.echo {"text":"approved"}',
+                provider_id="mock",
+                model="mock-1",
+                allowed_tools=["system.echo"],
+                tool_timeout_seconds=2,
+            )
+        )
+
+        request_id = None
+        async with asyncio.timeout(2):
+            async for event in container.agent.events(created.run_id):
+                if event.event == AgentEventType.permission_required:
+                    request_id = str(event.data["request_id"])
+                    break
+
+        assert request_id is not None
+        assert container.agent.resolve_permission(
+            created.run_id, request_id, "allow_once"
+        )
+        completed = await container.agent.wait(created.run_id)
+        assert completed.status == AgentRunStatus.completed
+        assert completed.tool_results[0].success is True
+
+    run(scenario())
+
+
+def test_step_limit_stops_repeated_agent_loop() -> None:
+    async def scenario() -> None:
+        container = build_container()
+        created = await container.agent.create_run(
+            AgentRunCreateRequest(
+                input='/tool system.echo {"text":"one step"}',
+                provider_id="mock",
+                model="mock-1",
+                allowed_tools=["system.echo"],
+                max_steps=1,
+            )
+        )
+
+        completed = await container.agent.wait(created.run_id)
+        assert completed.status == AgentRunStatus.failed
+        assert completed.error_code == "MAX_STEPS_EXCEEDED"
+        assert len(completed.tool_results) == 1
+
+    run(scenario())
+
+
+def test_token_budget_stops_agent_run() -> None:
+    async def scenario() -> None:
+        container = build_container()
+        created = await container.agent.create_run(
+            AgentRunCreateRequest(
+                input="hello budget",
+                provider_id="mock",
+                model="mock-1",
+                token_budget=1,
+            )
+        )
+
+        completed = await container.agent.wait(created.run_id)
+        assert completed.status == AgentRunStatus.failed
+        assert completed.error_code == "TOKEN_BUDGET_EXCEEDED"
+
+    run(scenario())
+
+
+def test_cancelling_permission_wait_cancels_run() -> None:
+    async def scenario() -> None:
+        container = build_container()
+        protected_tool = container.tools.get("system.echo")
+        protected_tool.definition.permission = "notes.write"
+        created = await container.agent.create_run(
+            AgentRunCreateRequest(
+                input='/tool system.echo {"text":"cancel"}',
+                provider_id="mock",
+                model="mock-1",
+                allowed_tools=["system.echo"],
+                tool_timeout_seconds=10,
+            )
+        )
+
+        async with asyncio.timeout(2):
+            while container.agent.get_run(created.run_id).status != AgentRunStatus.waiting_permission:
+                await asyncio.sleep(0)
+
+        cancelled = await container.agent.cancel(created.run_id)
+        await container.agent.wait(created.run_id)
+        assert cancelled.status == AgentRunStatus.cancelled
+        assert container.agent.get_run(created.run_id).cancelled is True
+
+    run(scenario())

backend/tests/test_api.py

@@ -28,7 +28,7 @@ def test_query_shells_are_empty_and_typed() -> None:
     assert notes.page.limit == 20
     assert skills.items == []
     assert plugins.items == []
-    assert providers.items == []
+    assert [provider.provider_id for provider in providers.items] == ["mock"]
     assert index.status == "idle"