feat: AI Agent Sandbox MCP Server v1を実装

Specifications、Design、ImplementationPlanの優先順位を整理し、単一Task実行モデル、typed option優先、設定可能なresource上限、local Ollamaを必須とするRelease Gateを文書化。

.NET 10/C# 14の5 production project、3 test project、E2E Clientを構築。typed YAML、en/ja locale、fixed/user prompt、stdioおよびloopback限定Streamable HTTP、agent_run/agent_status、Session、Ollama text/tool/Vision、TaskGraphとtoken accountingを実装。

Windows sandboxとしてfixed AppContainer、canonical/reparse検査、能力別ACL、path+SHA-256 executable approval、child-process restriction、Job Object、task journal、atomic file transaction、crash recoveryを実装。WFPのIPv4/IPv6 default denyとexact allow、dynamic session、temporary loopback exemption、管理者/BFE診断を追加。

Security/Recovery test、MCP/Ollama integration test、stdio/HTTP Operational E2E、Release Bundle生成・checksum・manifest・fresh extraction検査を追加。Requirement TraceabilityとPhase 0〜11の進捗、初回セットアップ可能なREADMEを整備。

Debug/Release/publish/objをrepository rootのbuild/へ集約し、旧project-local bin/objへの依存を除去。artifacts/とbuild/をGit管理外に設定し、clean checkoutでもsolution buildからE2E Clientまで生成可能にした。

3 files changed, 48 insertions, 0 deletions

diff --git a/src/Agent.Core/Sessions/AgentSession.cs b/src/Agent.Core/Sessions/AgentSession.cs
new file mode 100644
index 0000000..d561c8d
--- /dev/null
+++ b/src/Agent.Core/Sessions/AgentSession.cs
@@ -0,0 +1,26 @@
+namespace Agent.Core.Sessions;
+
+public sealed class AgentSession(Guid sessionId)
+{
+    private readonly object _sync = new();
+    private readonly List<ConversationMessage> _conversation = [];
+
+    public Guid SessionId { get; } = sessionId;
+    public DateTimeOffset CreatedAt { get; } = DateTimeOffset.UtcNow;
+    public DateTimeOffset LastAccessAt { get; private set; } = DateTimeOffset.UtcNow;
+
+    public IReadOnlyList<ConversationMessage> Conversation
+    {
+        get { lock (_sync) return _conversation.ToArray(); }
+    }
+
+    public void Append(ConversationMessage message)
+    {
+        ArgumentNullException.ThrowIfNull(message);
+        lock (_sync)
+        {
+            _conversation.Add(message);
+            LastAccessAt = DateTimeOffset.UtcNow;
+        }
+    }
+}
diff --git a/src/Agent.Core/Sessions/ConversationMessage.cs b/src/Agent.Core/Sessions/ConversationMessage.cs
new file mode 100644
index 0000000..9d48747
--- /dev/null
+++ b/src/Agent.Core/Sessions/ConversationMessage.cs
@@ -0,0 +1,3 @@
+namespace Agent.Core.Sessions;
+
+public sealed record ConversationMessage(string Role, string Content);
diff --git a/src/Agent.Core/Sessions/SessionStore.cs b/src/Agent.Core/Sessions/SessionStore.cs
new file mode 100644
index 0000000..59ea02c
--- /dev/null
+++ b/src/Agent.Core/Sessions/SessionStore.cs
@@ -0,0 +1,19 @@
+using System.Collections.Concurrent;
+
+namespace Agent.Core.Sessions;
+
+public sealed class SessionStore
+{
+    private readonly ConcurrentDictionary<Guid, AgentSession> _sessions = new();
+
+    public AgentSession Create()
+    {
+        while (true)
+        {
+            var session = new AgentSession(Guid.NewGuid());
+            if (_sessions.TryAdd(session.SessionId, session)) return session;
+        }
+    }
+
+    public bool TryGet(Guid sessionId, out AgentSession? session) => _sessions.TryGetValue(sessionId, out session);
+}