diff --git a/packages/support/acp-snapshot/README.i18n.yaml b/packages/support/acp-snapshot/README.i18n.yaml
index 338905642c..8742eb2d2a 100644
--- a/packages/support/acp-snapshot/README.i18n.yaml
+++ b/packages/support/acp-snapshot/README.i18n.yaml
@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/support/acp-snapshot/README.md
-README.md: 371ede587b84ba96770d4a2b1ee89b029d92dd25
-README.zh.md: f596f9021ae9b8c5973efafae7f7d695293b96e1
+README.md: 5e777c3ce6b46f0e61c47f330566fe0acae41a9b
+README.zh.md: 40801980600fb8d55210d2c59eeef4468aa9483f
diff --git a/packages/support/acp-snapshot/README.md b/packages/support/acp-snapshot/README.md
index b42551b8b7..5e777c3ce6 100644
--- a/packages/support/acp-snapshot/README.md
+++ b/packages/support/acp-snapshot/README.md
@@ -51,7 +51,7 @@ defineAcpSnapshotSuite({
 })
 ```
 
-A scenario booting a differently-composed tree sets its own `configPath` (an overlay whose basename still ends in `cordis.yml`, so the bin's replay swap finds the sibling `*cordis.snapshot.yml`) and, when that composition changes the request header, its own `headerClass` with its own pinning scenario — the acp-agent example's Code Mode and filesystem scenarios are templates. `workspaceParent` moves the generated cwd outside the platform temp area when temporary-directory grants are themselves under test; the harness still owns and removes only the generated child. A scenario's committed `workspace/` is copied into that child first, then `prepareWorkspace` runs against the generated cwd before the agent starts. Reserve this hook for fixtures Git cannot represent portably, keep ordinary seeds in `workspace/`, and pair it with `posixOnly` when the generated paths are invalid on Windows.
+A scenario booting a differently-composed tree sets its own `configPath` (an overlay whose basename still ends in `cordis.yml`, so the bin's replay swap finds the sibling `*cordis.snapshot.yml`) and, when that composition changes the request header, its own `headerClass` with its own pinning scenario — the acp-agent example's Code Mode and filesystem scenarios are templates. Default generated workspaces are stored in session fixtures as `{{cwd}}` so platform temp roots and random basenames do not affect recordings; `workspaceParent` moves the generated cwd outside the platform temp area when temporary-directory grants are themselves under test, keeps that explicit path in the fixture, and remains parent-owned while the harness removes only the generated child. A scenario's committed `workspace/` is copied into that child first, then `prepareWorkspace` runs against the generated cwd before the agent starts. Reserve this hook for fixtures Git cannot represent portably, keep ordinary seeds in `workspace/`, and pair it with `posixOnly` when the generated paths are invalid on Windows.
 
 A pin owns its generated `system-prompt.expected.md` or `tool-schemas.expected.json` by default; `systemPromptSource` and `toolSchemasSource` name another pin when the complete corresponding sequence is identical, so each distinct version is committed once. The pin's `session.jsonl` stores `"system":"{{system}}","tools":"{{tools}}"` while retaining config, reason, and any model-visible prefix. A pin with legitimate mid-run header changes declares `expectedHeaderChanges`; a shared source must declare the same count, and record/refresh rejects claimants that generate different bytes.
 
diff --git a/packages/support/acp-snapshot/README.zh.md b/packages/support/acp-snapshot/README.zh.md
index eeb1179054..4080198060 100644
--- a/packages/support/acp-snapshot/README.zh.md
+++ b/packages/support/acp-snapshot/README.zh.md
@@ -51,7 +51,7 @@ defineAcpSnapshotSuite({
 })
 ```
 
-启动不同组合树的场景会设置自己的 `configPath`（一个 basename 仍以 `cordis.yml` 结尾的 overlay，使 bin 的回放交换可找到同级 `*cordis.snapshot.yml`）；当该组合改变请求 header 时，还会设置自己的 `headerClass` 和 pin 场景，acp-agent 示例的 Code Mode 与文件系统场景是模板。当临时目录授权自身待测时，`workspaceParent` 将生成 cwd 移出平台临时区域；harness 仍只拥有并移除生成的子级。场景签入的 `workspace/` 会先复制到该子级，随后 `prepareWorkspace` 在 agent 启动前针对生成 cwd 运行。此 hook 仅用于 Git 无法跨平台表示的 fixture；普通种子应留在 `workspace/` 中，而生成路径在 Windows 上无效时还必须搭配 `posixOnly`。
+启动不同组合树的场景会设置自己的 `configPath`（一个 basename 仍以 `cordis.yml` 结尾的 overlay，使 bin 的回放交换可找到同级 `*cordis.snapshot.yml`）；当该组合改变请求 header 时，还会设置自己的 `headerClass` 和 pin 场景，acp-agent 示例的 Code Mode 与文件系统场景是模板。默认生成的 workspace 在会话 fixture 中存储为 `{{cwd}}`，使平台临时根目录和随机 basename 不影响录制结果；当临时目录授权自身待测时，`workspaceParent` 将生成 cwd 移出平台临时区域，在 fixture 中保留该显式路径，并仍归父级所有，而 harness 只移除生成的子级。场景签入的 `workspace/` 会先复制到该子级，随后 `prepareWorkspace` 在 agent 启动前针对生成 cwd 运行。此 hook 仅用于 Git 无法跨平台表示的 fixture；普通种子应留在 `workspace/` 中，而生成路径在 Windows 上无效时还必须搭配 `posixOnly`。
 
 每个 pin 默认拥有其生成的 `system-prompt.expected.md` 或 `tool-schemas.expected.json`；当完整的对应序列相同时，`systemPromptSource` 和 `toolSchemasSource` 指定另一个 pin 作为来源，因此每个不同版本只提交一次。该 pin 的 `session.jsonl` 存储 `"system":"{{system}}","tools":"{{tools}}"`，同时保留配置、原因和任何模型可见前缀。具有合法运行中 header 变更的 pin 声明 `expectedHeaderChanges`；共享来源必须声明相同的 header 变更数量，录制/刷新会拒绝生成不同字节的共享引用方。