The GitHub Copilot SDK just shipped a new feature: optional memory configuration on session create and resume. Here is what it does, and how it is different from persisted sessions.GitHub Copilot SDK 刚刚发布了一项新功能：在创建和恢复会话时支持可选的内存配置。以下是它的功能介绍，以及它与持久化会话的区别。
The wrong mental model first首先纠正错误的思维模型
When I heared "session memory" my first thought was "persisted sessions" — the ResumeSessionAsync flow that lets you reload an existing session by ID and continue where you left off. That is not what this is. Persisted sessions are about durability of the conversation itself: close the app, reopen it, pick up the thread. Memory configuration is something different.当我听到“会话记忆”时，我的第一反应是“持久化会话”——即 ResumeSessionAsync 流程，它允许你通过 ID 重新加载现有会话并从上次中断的地方继续。但它并不是这个意思。持久化会话关注的是对话本身的持久性：关闭应用、重新打开，然后继续之前的对话。而内存配置则是另一回事。
What memory configuration actually does内存配置的实际作用
Memory is a feature of the Copilot runtime that lets the agent read and write facts across turns — a kind of long-running knowledge store that the agent can consult and update during a session. Think of it as the agent's notepad, not the conversation log.内存是 Copilot 运行时的一项功能，允许智能体在不同轮次间读取和写入事实信息——这是一种智能体可以在会话期间查阅和更新的长期知识存储。可以把它想象成智能体的记事本，而不是对话日志。
The new MemoryConfiguration type exposes a single Enabled flag today. You opt in per session, on both create and resume:新的 MemoryConfiguration 类型目前仅公开了一个 Enabled 标志。你需要在创建和恢复会话时分别进行选择性启用：
var session = await client.CreateSessionAsync(new SessionConfig
{
Model = "gpt-4o",
Memory = new MemoryConfiguration { Enabled = true }
});That's it. The SDK serialises it as { "memory": { "enabled": true } } on the wire. When you leave Memory unset, the field is omitted entirely and the runtime applies its own default.就是这样。SDK 会将其序列化为 { "memory": { "enabled": true } } 进行传输。如果你不设置 Memory，该字段将被完全省略，运行时将应用其默认设置。
Now we can ask our agent to remember stuff:现在我们可以让智能体记住一些事情了：
The mode-based default matters基于模式的默认值很重要
There is a subtle default you need to understand. The SDK has two client modes:有一个你需要理解的微妙默认设置。SDK 有两种客户端模式：
CopilotClientMode.CopilotCli(the default):Memoryis left unset. The runtime decides. CopilotClientMode.CopilotCli（默认）：内存保持未设置状态。由运行时决定。CopilotClientMode.Empty:Memorydefaults to disabled unless you explicitly set it. CopilotClientMode.Empty：除非你显式设置，否则内存默认为禁用。
A caller-supplied value always wins in either mode. If you are building an app on Empty mode and you want memory, you must opt in explicitly. The runtime will not silently enable it for you.在任何模式下，调用者提供的值总是优先。如果你正在 Empty 模式下构建应用并希望使用内存，则必须显式启用它。运行时不会为你静默启用。
Persisted sessions vs. memory: the actual difference持久化会话与内存：真正的区别
| Persisted sessions | Memory configuration | |
| What it stores | The full conversation thread | Facts/notes the agent writes |
| Lifetime | Until you delete the session | Managed by the runtime |
| API surface | ResumeSessionAsync(sessionId) |
SessionConfig.Memory |
| Scope | Cross-process, cross-restart | Within the session, agent-controlled |
A persisted session lets you reload the conversation. Memory lets the agent remember things across turns within — and potentially across — sessions, depending on how the runtime implements it.持久化会话允许你重新加载对话。内存则允许智能体在会话内（甚至根据运行时的实现方式，在跨会话间）记住事物。
You can use both at the same time: resume a persisted session with memory enabled, and the agent brings its notepad along.你可以同时使用两者：在启用内存的情况下恢复持久化会话，智能体就会带上它的记事本。
Resuming with memory恢复带有内存的会话
ResumeSessionAsync also accepts the memory configuration:ResumeSessionAsync 也接受内存配置：
var session = await client.ResumeSessionAsync(sessionId, new ResumeSessionConfig
{
Memory = new MemoryConfiguration { Enabled = true }
});This means you can control memory independently of whether the session is new or resumed. Useful if you want to enable memory for an existing session that was originally created without it.这意味着你可以独立于会话是新建还是恢复来控制内存。如果你想为最初创建时未启用内存的现有会话启用内存，这将非常有用。
More information更多信息
PR #1617 — SDK: add optional memory configuration to session create and resumePR #1617 — SDK：在会话创建和恢复中添加可选的内存配置
GitHub Copilot SDK Deep Dive: CopilotClientModeGitHub Copilot SDK 深度解析：CopilotClientMode