diff --git a/design/03-rust-web/process/3-19-rust-web-browser-runtime-module-extraction-v1.md b/design/03-rust-web/process/3-19-rust-web-browser-runtime-module-extraction-v1.md
index 8fa94981..91ee4429 100644
--- a/design/03-rust-web/process/3-19-rust-web-browser-runtime-module-extraction-v1.md
+++ b/design/03-rust-web/process/3-19-rust-web-browser-runtime-module-extraction-v1.md
@@ -497,6 +497,9 @@ node scripts/task479-local-folder-markdown-resource-lifecycle-smoke.js
   - pdf/code -> 对应 lightweight viewer
   - office -> OnlyOffice path builder
 - [ ] 从 `SIDEBAR_TREE_JS` 中迁出本地文件夹上传目标计算和 adapter 调用；资源归属语义仍由 Rust API / kernel 合同决定。
+  - 2026-05-24 / `reasonix-2026-05-24T15-17-16-430Z-18054487` 只读审计：`leptos-tiptap` 只应发出上传 intent；本地 Markdown 路径、`rootUri`、`/api/local-folder/files/open` URL、`markdownRelativePath` 与真实上传落盘都归本设计的 shell host runtime。
+  - 下一刀低风险候选：`resolveEditorUploadContext`、`editorRootFromUploadOptions`、`openEditorUploadFilePicker`，优先保持调用 `uploadFilesWithResolvedTarget`，不同时迁上传主流程。
+  - 暂不迁：`uploadFileToMediaAsset`、`uploadFilesWithResolvedTarget`、`insertUploadedAssetIntoEditor`。这些函数同时涉及 API POST、file tree refresh、Tiptap chain 插入、OnlyOffice/resource tab，需在后续批次继续拆边界。
 - [ ] 保持现有 smoke：
   - `node scripts/task472-side-target-secondary-pane-smoke.js`
   - `node scripts/task479-local-folder-markdown-resource-lifecycle-smoke.js`
diff --git a/design/05-editor-mainline/process/5-28-leptos-tiptap-editor-runtime-module-extraction-v1.md b/design/05-editor-mainline/process/5-28-leptos-tiptap-editor-runtime-module-extraction-v1.md
index d3f0fcf8..2613a645 100644
--- a/design/05-editor-mainline/process/5-28-leptos-tiptap-editor-runtime-module-extraction-v1.md
+++ b/design/05-editor-mainline/process/5-28-leptos-tiptap-editor-runtime-module-extraction-v1.md
@@ -138,10 +138,15 @@ rust/spikes/leptos-tiptap-spike/src/
 
 ### P3：抽出附件上传与本地 Markdown 路径
 
-- [ ] 新增 `editor_runtime/attachment_upload.rs`。
+- [x] 新增 `editor_runtime/attachment_upload.rs`。
 - [ ] 新增 `editor_runtime/local_markdown_paths.rs`。
-- [ ] 迁出 slash 上传附件、图片、Office/PDF/code 文件的编辑器内插入逻辑。
-- [ ] 明确 editor 只负责插入附件链接/块，资源保存位置和归属仍由 shell/Rust API 合同决定。
+  - 2026-05-24 复核：`local_markdown_paths.rs` 不应落在 `leptos-tiptap` 内部；本地 Markdown 路径、`rootUri`、`/api/local-folder/files/open` URL 和上传落盘归 `03-rust-web` 的 shell host runtime / `local-upload-runtime.js`。
+- [x] 迁出 slash 上传附件、图片的编辑器 intent。
+  - `dispatch_editor_upload_request(kind, accept)` 已迁入 `attachment_upload.rs`。
+  - `SlashActionKind::Image` / `UploadAttachment` 仍留在 slash menu 基础结构中，只调用 editor intent。
+- [ ] 迁出 Office/PDF/code 文件的编辑器内插入逻辑。
+  - 当前实际插入链路在 `layout.rs` / `local-upload-runtime.js`，不是 editor runtime；后续由 `03-rust-web` 继续收口。
+- [x] 明确 editor 只负责发起上传 intent；资源保存位置和归属仍由 shell/Rust API 合同决定。
 - [ ] 覆盖：
   - 上传第一个/第二个附件后链接仍可点击。
   - 刷新后链接不退化为普通外链。
@@ -347,6 +352,45 @@ Codex 主控复核：
 - `cargo test --manifest-path rust/spikes/leptos-tiptap-spike/Cargo.toml standalone_mindmap_object_uses_isolated_draft_identity`
 - 阻塞原因：lib test 编译阶段命中既有 `slash_menu_css_uses_viewport_overlay_layer` 中 `STYLE` 未定义；HEAD 中该测试已引用 `STYLE`，而实际常量名为 `SPIKE_STYLE`。该问题不属于本批拆分，已记录为后续单独处理。
 
+### 10.4 Batch 3 第一刀执行记录（2026-05-24）
+
+Reasonix read-only audit：
+
+- run id: `reasonix-2026-05-24T15-17-16-430Z-18054487`
+- worker worktree: `/mnt/Data1T/mnote-wt-5-28-upload-boundary-b3`
+- handoff: `/home/lix/.codex/runtime/reasonix-coding-worker/reasonix-2026-05-24T15-17-16-430Z-18054487/process-handoff.md`
+- 类型：只读审计，主控已读取 Hindsight recall、`process-handoff.md`、`process-handoff.json`。
+
+采纳结论：
+
+- 当前上传链路应保持 `editor intent -> CustomEvent -> shell pickup`。
+- `attachment_upload.rs` 只承接 `dispatch_editor_upload_request(kind, accept)` 这一类编辑器 intent，不迁入真实上传、文件选择器、API POST、资源归属或插入链接主流程。
+- `local_markdown_paths.rs` 暂不在 `leptos-tiptap` 内创建；本地 Markdown 路径、`rootUri`、`/api/local-folder/files/open` URL、`markdownRelativePath` 与落盘语义归 `03-rust-web` shell host runtime / `local-upload-runtime.js`。
+
+采纳内容：
+
+- 新增 `editor_runtime/attachment_upload.rs`，迁出 `dispatch_editor_upload_request(kind, accept)`。
+- `src/lib.rs` 的 `run_slash_action` 继续保留 `SlashActionKind::Image` / `UploadAttachment` 的 slash menu 决策，只调用 `attachment_upload` 发出上传 intent。
+- `src/lib.rs` 不再直接构造 `mnote:editor-upload-request`。
+
+已通过验证：
+
+- `cargo fmt --manifest-path rust/Cargo.toml --all --check`
+- `cargo check --manifest-path rust/spikes/leptos-tiptap-spike/Cargo.toml`（35 个既有 warning）
+- `cargo build --manifest-path rust/spikes/leptos-tiptap-spike/Cargo.toml --target wasm32-unknown-unknown --release`（35 个既有 warning）
+- `wasm-bindgen rust/spikes/leptos-tiptap-spike/target/wasm32-unknown-unknown/release/mnote_leptos_tiptap_spike.wasm --target web --out-dir rust/spikes/leptos-tiptap-spike/generated/island --out-name mnote-leptos-tiptap-spike-island`
+- `node scripts/task488-local-attachment-link-delete-undo-smoke.js`
+  - 结果：`ok=true`
+  - 证据：`tmp/task488-local-attachment-link-delete-undo-smoke/result.json`
+- `node scripts/task479-local-folder-markdown-resource-lifecycle-smoke.js`
+  - 结果：`ok=true`
+  - 证据：命令 stdout JSON，覆盖 `editor-upload-to-page-resource-dir`、`filetree-folder-drop-to-target`、`broken-link-after-real-file-delete`、`direct-attach-open-without-active-md`、`editor-delete-one-attachment-preserves-adjacent` 等检查。
+
+后续归属：
+
+- `resolveEditorUploadContext`、`editorRootFromUploadOptions`、`openEditorUploadFilePicker` 等 shell-side DOM/context 探针适合进入 `03-rust-web` 的 `local-upload-runtime.js` 后续批次。
+- `uploadFileToMediaAsset`、`uploadFilesWithResolvedTarget`、`insertUploadedAssetIntoEditor` 仍是高耦合主流程，暂不迁入 editor runtime。
+
 ## 11. 测试与验收
 
 ### Rust 检查
diff --git a/rust/spikes/leptos-tiptap-spike/generated/island/mnote-leptos-tiptap-spike-island.js b/rust/spikes/leptos-tiptap-spike/generated/island/mnote-leptos-tiptap-spike-island.js
index 14ea47e7..4aed409a 100644
--- a/rust/spikes/leptos-tiptap-spike/generated/island/mnote-leptos-tiptap-spike-island.js
+++ b/rust/spikes/leptos-tiptap-spike/generated/island/mnote-leptos-tiptap-spike-island.js
@@ -1284,7 +1284,7 @@ function __wbg_get_imports() {
             return ret;
         },
         __wbindgen_cast_0000000000000006: function(arg0, arg1) {
-            // Cast intrinsic for `Closure(Closure { owned: true, function: Function { arguments: [NamedExternref("KeyboardEvent")], shim_idx: 758, ret: Unit, inner_ret: Some(Unit) }, mutable: true }) -> Externref`.
+            // Cast intrinsic for `Closure(Closure { owned: true, function: Function { arguments: [NamedExternref("KeyboardEvent")], shim_idx: 745, ret: Unit, inner_ret: Some(Unit) }, mutable: true }) -> Externref`.
             const ret = makeMutClosure(arg0, arg1, wasm_bindgen__convert__closures_____invoke__hd90af689bc3e71bf);
             return ret;
         },
diff --git a/rust/spikes/leptos-tiptap-spike/generated/island/mnote-leptos-tiptap-spike-island_bg.wasm b/rust/spikes/leptos-tiptap-spike/generated/island/mnote-leptos-tiptap-spike-island_bg.wasm
index efdf6d05..4a721bf9 100644
Binary files a/rust/spikes/leptos-tiptap-spike/generated/island/mnote-leptos-tiptap-spike-island_bg.wasm and b/rust/spikes/leptos-tiptap-spike/generated/island/mnote-leptos-tiptap-spike-island_bg.wasm differ
diff --git a/rust/spikes/leptos-tiptap-spike/src/editor_runtime/attachment_upload.rs b/rust/spikes/leptos-tiptap-spike/src/editor_runtime/attachment_upload.rs
new file mode 100644
index 00000000..0958228d
--- /dev/null
+++ b/rust/spikes/leptos-tiptap-spike/src/editor_runtime/attachment_upload.rs
@@ -0,0 +1,21 @@
+use serde_json::json;
+use web_sys::{window, CustomEvent, CustomEventInit};
+
+pub(crate) fn dispatch_editor_upload_request(kind: &str, accept: &str) -> Result<(), String> {
+    let win = window().ok_or_else(|| "当前浏览器窗口不可用".to_string())?;
+    let detail = json!({
+        "kind": kind,
+        "accept": accept,
+        "multiple": true,
+        "insertIntoEditor": true,
+    });
+    let detail =
+        serde_wasm_bindgen::to_value(&detail).map_err(|err| format!("构造上传请求失败：{err}"))?;
+    let init = CustomEventInit::new();
+    init.set_detail(&detail);
+    let event = CustomEvent::new_with_event_init_dict("mnote:editor-upload-request", &init)
+        .map_err(|_| "构造上传事件失败".to_string())?;
+    win.dispatch_event(&event)
+        .map(|_| ())
+        .map_err(|_| "派发上传事件失败".to_string())
+}
diff --git a/rust/spikes/leptos-tiptap-spike/src/editor_runtime/mod.rs b/rust/spikes/leptos-tiptap-spike/src/editor_runtime/mod.rs
index 2f2e0c27..4eb1a916 100644
--- a/rust/spikes/leptos-tiptap-spike/src/editor_runtime/mod.rs
+++ b/rust/spikes/leptos-tiptap-spike/src/editor_runtime/mod.rs
@@ -1,4 +1,5 @@
 pub(crate) mod attachment_links;
+pub(crate) mod attachment_upload;
 pub(crate) mod command_sync;
 pub(crate) mod history_safe_commands;
 pub(crate) mod persistence;
diff --git a/rust/spikes/leptos-tiptap-spike/src/lib.rs b/rust/spikes/leptos-tiptap-spike/src/lib.rs
index fba668ea..ed16ce9e 100644
--- a/rust/spikes/leptos-tiptap-spike/src/lib.rs
+++ b/rust/spikes/leptos-tiptap-spike/src/lib.rs
@@ -20,6 +20,7 @@ use web_sys::{
     HtmlInputElement, MouseEvent, Node, RequestInit, RequestMode, Response, WheelEvent,
 };
 
+use editor_runtime::attachment_upload::dispatch_editor_upload_request;
 use editor_runtime::command_sync::{
     read_editor_snapshot, sync_editor_outputs, sync_persisted_editor_command,
 };
@@ -7134,25 +7135,6 @@ fn table_option_checked(document: &Value, action: TableOptionAction) -> bool {
     }
 }
 
-fn dispatch_editor_upload_request(kind: &str, accept: &str) -> Result<(), String> {
-    let win = window().ok_or_else(|| "当前浏览器窗口不可用".to_string())?;
-    let detail = json!({
-        "kind": kind,
-        "accept": accept,
-        "multiple": true,
-        "insertIntoEditor": true,
-    });
-    let detail =
-        serde_wasm_bindgen::to_value(&detail).map_err(|err| format!("构造上传请求失败：{err}"))?;
-    let init = CustomEventInit::new();
-    init.set_detail(&detail);
-    let event = CustomEvent::new_with_event_init_dict("mnote:editor-upload-request", &init)
-        .map_err(|_| "构造上传事件失败".to_string())?;
-    win.dispatch_event(&event)
-        .map(|_| ())
-        .map_err(|_| "派发上传事件失败".to_string())
-}
-
 fn run_slash_action(
     editor: TiptapEditorHandle,
     action: SlashActionKind,