让fork sub agent支持指定模式使用.

[Jssly]

起因是主会话用的标准模式, 在需求确认后, 会对文件内容进行大幅度修改时, 但标准模式一来一回的方式会消耗大量token,而且慢. 而在PTC模式下,通过编程一次性的操作,可以快速完成并省token. 所以希望在主会话中fork agent 并指定为PTC模式运行. 但现在dsh fork agent只能自动继承父会话的模式, 不能手动指定...

我看了一下代码, 其实只要好小的改动就能实现fork agent指定模式运行:

tool-subagent (config: presentation: 'ptc') ← 新增字段，模型/配置层
│ request
▼
subagent-in-process-driver: startInProcessRun
│ setup(childCtx) ─┐
▼ ▼
child-agent.ts: applyChildComposition(childCtx, parent, composition)
├─ composeFrom(childCtx, parent.ctx) ← 已有：加入父 preset
├─ persona / toolFilter ← 已有：只穿这两个
└─ 新增: childCtx.tools.presentAs('ptc') ← 需要加的：子代理自己 scope 的声明

具体来说：

packages/subagent/subagent/src/child-agent.ts — ChildComposition 接口加一个可选 presentation?: 'ptc'（或 mode），在 applyChildComposition 里、composeFrom 之后调 childCtx.tools.presentAs('ptc')。modeFor 就近优先，子代理自己 scope 的声明会盖过父 preset standing scope 的（standard 没有声明，native 是默认值），父会话完全不受影响。
packages/subagent/tool-subagent/src/index.ts — Config schema 加同名字段并透传（provider: fork 那一行也能用 config 配死，不用暴露给模型）。
packages/subagent/subagent/src/continuation.ts（约 1232 行） — 同一 seam 的第二处调用点。标准 preset 里 subagent_fork 是 backgroundMode: continuable，续跑时走 continuation manager，也要同步穿这个字段，否则续跑的子代理会掉回 native。
不需要动 modeFor/presentAs/agent-presets 本身——机制和测试（"一个 agent PTC、旁边 native"）都已经证明是通的。

希望DSH官方可以支持...这样就不用自己改源码了

[argszero]

Solid analysis — I verified the source and the seam is exactly where you say, and I'd strongly support this upstream. Let me confirm the pieces:

The mechanism is already there. presentAs(mode) exists on the tools registry (packages/core/tools/src/index.ts:938), and modeFor(context.scope) (:892) resolves a scope's presentation mode, falling back to the deployment default (:808 "Presentation for scopes that declare none; presentAs shadows it per scope"). So the "per-scope presentAs shadows the default" model is fully in place — as you note, the tests ("one agent PTC, neighbor native") prove it works.

The gap is purely the composition threading. ChildComposition (packages/subagent/subagent/src/child-agent.ts:159) currently carries only persona?: string and toolFilter? — no presentation/mode field. applyChildComposition (:199) does composeFrom(childCtx, parent.ctx) then applies persona/toolFilter; adding an optional presentation?: ToolPresentationMode that calls childCtx.tools.presentAs('ptc') after composeFrom is exactly the right placement. And as you said, modeFor is "nearest scope wins," so the child's own declaration overrides the parent preset standing scope — parent session unaffected. Clean and surgical.

The continuation seam is the sharp edge — good catch. subagent_fork is backgroundMode: continuable in the standard preset; the continuable child lives on in continuation.ts, so the same field must be threaded through that second call site or a resumed child silently drops back to native. That's the kind of subtlety that makes this more than a one-line change, and it's worth calling out explicitly in the PR.

This is the same shape as a gap I've seen upstream for reasoningEffort. I maintain @argszero/cordis-plugin-subagent-effort precisely because per-call subagent options (effort/mode) weren't threadable — the standard tool-subagent only inherited the parent's setting; there was no way to set it per-fork. That plugin exists as a community stopgap for reasoningEffort; your presentation: 'ptc' is the analogous option for mode, and it's a much cleaner fit as an in-tree feature (a presentation/mode field on the tool-subagent config + ChildComposition). Upstreaming it would close the "per-call subagent config" gap properly, rather than working around it plugin-side.

One small thing worth deciding early: whether to call it presentation or mode — presentAs(mode) takes a ToolPresentationMode ('native' | 'ptc' | ...), and the config catalog already refers to it as "mode" (the dsh-tools mode config). A presentation field that takes a ToolPresentationMode value is consistent with the existing presentAs naming; I'd lean toward matching the API it wraps. Happy to help test a patch if you open one.

[Jssly]

I've actually used your plugin before. Unfortunately, DSH doesn't accept pull requests. You could actually add a ctx.on('agent/created') event to your plugin to override DSH's native fork sub-agent logic, which would allow you to specify the mode for running.

[Jssly]

我刚research多了一下, 只改入口只能算一个简单patch(方便其它插件启动指定模式的fork sub agent), 如果要让AI支持自然语言指定模式,还需要改

段	文件	内容
1. schema	packages/subagent/tool-subagent/src/index.ts	defineTool 的 parameters 加 presentation?: { type:'string', enum:['native','ptc','both'] }；并改 description 措辞
2. 请求透传	packages/subagent/subagent/src/types.ts + tool 构造 request 处	ResolvedSubagentStartRequest 加 presentation?，request.presentation
3. 子代理组合,	packages/subagent/subagent/src/child-agent.ts	ChildComposition 加 presentation?；applyChildComposition 在 composeFrom 后调 childCtx.tools.presentAs(...)
4. 驱动透传	packages/subagent/subagent-in-process-driver/src/index.ts	setup 里把 request.presentation 传进 composition
5. capability	subagent-fork-in-process（及 spawn）	capabilities 加 presentation: true
6. continuable 持久化	packages/subagent/subagent/src/continuation.ts	descriptor与 composition 记录 加 presentation