diff --git a/README.md b/README.md
index c5e8ffd..217296c 100644
--- a/README.md
+++ b/README.md
@@ -80,6 +80,13 @@ hip 全链路可用；0811 与 0812 最终快照实机 boot 验证通过（见
 
 ## 更新记录 / Changelog
 
+### 2026-09-08 · v0.1.23 — 大段文本粘贴自动转附件（基于上游 v0.1.22，PR #1）
+
+- **新功能**：在输入框粘贴**纯文本**时，超过阈值（默认 **1000 字符**，设置面板可调 关闭/1000/2000/5000）或超过 **20 行**的内容不再插入输入框，而是自动转为 `paste_text.txt` 附件芯片——复用粘贴文件全管道（`paste_image`/`paste_file` 同族命名，重名自动加 `(2)`、`(3)…` 序号，发送时复制进 `.dsh/tmp/attachments/`，气泡自动折叠）
+- **拦截位置**：document capture 阶段，先于 composer 自身的 paste 监听（兼容 Lexical contenteditable 与 textarea 两代 composer），只对落在 composer 上的粘贴生效，不影响队列编辑器/设置搜索框等其他输入
+- **设置面板**：附件设置页新增「大段文本粘贴自动转附件」阈值下拉框（localStorage 持久化）
+- 已提 PR：[lhh010/dsh-paste-input#1](https://github.com/lhh010/dsh-paste-input/pull/1)
+
 ### 2026-09-04 · v0.1.19 — 声明支持 dsh-v0.1.3-alpha.1
 
 - **验证**：0.1.3 破坏性变更集中在 host/session 侧（SessionHandle / session format v2），composer/输入面实测无影响；npm 未发布，源码宿主实机验证（粘贴入框/悬停预览/查看器正常），无需代码改动
diff --git a/lib/client.js b/lib/client.js
index 7355f00..32ef2da 100644
--- a/lib/client.js
+++ b/lib/client.js
@@ -19,6 +19,29 @@ window.__ModuleLoader__.load({
       if (!next) { try { window.sessionStorage.removeItem(PERSIST_KEY); } catch (e2) { /* best effort */ } }
       else persistSnapshot();
     }
+    // --- 大段文本粘贴阈值：超过阈值的纯文本粘贴不插入输入框，自动转为
+    // paste_text.txt 附件芯片（复用粘贴文件管道；重名由 add() 的
+    // uniqueLabel 自动加 (2)、(3)…）。localStorage 持久化，设置面板可调。
+    // 行数规则独立于阈值：超过 TEXT_LINE_LIMIT 行一律视为大段文本（阈值开启时）。
+    const TEXT_THRESHOLD_KEY = 'dsh-paste-input.textThreshold';
+    const TEXT_LINE_LIMIT = 20;
+    const TEXT_THRESHOLD_DEFAULT = '1000';
+    const textThresholdOptions = [
+      { value: '0', label: '关闭' },
+      { value: '1000', label: '1000 字符（默认）' },
+      { value: '2000', label: '2000 字符' },
+      { value: '5000', label: '5000 字符' },
+    ];
+    function textThresholdRaw() {
+      try {
+        const raw = window.localStorage.getItem(TEXT_THRESHOLD_KEY);
+        return raw === null ? TEXT_THRESHOLD_DEFAULT : raw;
+      } catch { return TEXT_THRESHOLD_DEFAULT; }
+    }
+    function textThreshold() {
+      const n = Number(textThresholdRaw());
+      return Number.isFinite(n) && n > 0 ? n : 0;
+    }
     function persistSnapshot() {
       if (!persistRecords) return;
       try {
@@ -107,6 +130,10 @@ window.__ModuleLoader__.load({
       .dshca-settings-action[data-danger=true]{color:var(--dsw-alias-state-error-primary)}
       .dshca-settings-action:disabled{opacity:.45;cursor:default}
       .dshca-settings-status{color:var(--dsw-alias-label-secondary);font-size:12px;line-height:18px}
+      .dshca-settings-textpaste{display:flex;flex-direction:column;gap:8px;padding:16px;border:1px solid var(--dsw-alias-border-l1);border-radius:14px;background:var(--dsw-alias-bg-layer-1)}
+      .dshca-settings-textpaste-row{display:flex;align-items:center;justify-content:space-between;gap:12px}
+      .dshca-settings-textpaste-label{font-size:13px}
+      .dshca-settings-select{height:32px;padding:0 8px;border:1px solid var(--dsw-alias-border-l1);border-radius:9px;background:var(--dsw-alias-bg-base);color:var(--dsw-alias-label-primary);font:inherit;font-size:13px;cursor:pointer}
       @media(max-width:720px){.dshca-settings-card{grid-template-columns:1fr}.dshca-dock{width:calc(100% - 16px)}}
       .dshca-notice-overlay{position:fixed;inset:0;z-index:100;display:flex;align-items:center;justify-content:center;background:rgba(0,0,0,.45)}
       .dshca-notice{width:min(420px,calc(100vw - 48px));box-sizing:border-box;padding:18px;border:1px solid var(--dsw-alias-border-l1);border-radius:14px;background:var(--dsw-alias-bg-base);box-shadow:var(--dsw-shadow-lv3);display:flex;flex-direction:column;gap:10px;color:var(--dsw-alias-label-primary)}
@@ -587,7 +614,7 @@ window.__ModuleLoader__.load({
       title.textContent = '粘贴文件提示';
       const copy = document.createElement('div');
       copy.className = 'dshca-notice-copy';
-      copy.textContent = '你粘贴了图片或文件。DSH Paste Input 会把它们复制到当前会话工作区的临时附件目录（.dsh/tmp/attachments/），并在发送时随消息一起交给模型。';
+      copy.textContent = '你粘贴了图片或文件。DSH Paste Input 会把它们复制到当前会话工作区的临时附件目录（.dsh/tmp/attachments/），并在发送时随消息一起交给模型。在输入框粘贴的大段纯文本也会自动转为 paste_text.txt 附件（阈值可在设置面板调整）。';
       const label = document.createElement('label');
       label.className = 'dshca-notice-check';
       const checkbox = document.createElement('input');
@@ -754,6 +781,8 @@ window.__ModuleLoader__.load({
         loading: '正在读取当前会话附件…',
         cleanedCurrent: result => `已清理当前会话 ${result.deletedFiles} 个文件（${humanBytes(result.deletedBytes)}）。`,
         cleanedWorkspace: result => `已清理当前工作区 ${result.deletedSessionDirectories} 个会话目录、${result.deletedFiles} 个文件（${humanBytes(result.deletedBytes)}）。`,
+        textPasteLabel: '大段文本粘贴自动转附件',
+        textPasteCopy: '在输入框粘贴纯文本时，超过所选字符数（或超过 20 行）的内容不再插入输入框，而是自动转为 paste_text.txt 附件芯片——与粘贴图片同一管道，同名自动加 (2)、(3)… 序号。选择「关闭」则所有文本粘贴保持原样。',
       } : {
         nav: 'Multimedia input',
         title: 'Multimedia input & file management',
@@ -775,6 +804,8 @@ window.__ModuleLoader__.load({
         loading: 'Reading attachments for the active session…',
         cleanedCurrent: result => `Removed ${result.deletedFiles} files from the active session (${humanBytes(result.deletedBytes)}).`,
         cleanedWorkspace: result => `Removed ${result.deletedFiles} files from ${result.deletedSessionDirectories} session directories in this workspace (${humanBytes(result.deletedBytes)}).`,
+        textPasteLabel: 'Paste large text as attachment',
+        textPasteCopy: 'When you paste plain text into the composer, content beyond the chosen character count (or 20 lines) becomes a paste_text.txt attachment chip instead of being inserted — same pipeline as pasted images, with (2), (3)… suffixes on name collisions. Choose Off to keep all text pastes as-is.',
       };
     }
 
@@ -800,6 +831,11 @@ window.__ModuleLoader__.load({
       const [status, setStatus] = React.useState(sessionId === undefined ? copy.noSession : copy.loading);
       const [busy, setBusy] = React.useState(false);
       const [confirming, setConfirming] = React.useState(null);
+      const [textThresholdState, setTextThresholdState] = React.useState(textThresholdRaw());
+      const onTextThresholdChange = next => {
+        setTextThresholdState(next);
+        try { window.localStorage.setItem(TEXT_THRESHOLD_KEY, next); } catch { /* best effort */ }
+      };
 
       const load = React.useCallback(async (signal) => {
         if (sessionId === undefined) {
@@ -878,6 +914,15 @@ window.__ModuleLoader__.load({
           h('div', { className: 'dshca-stat' }, h('strong', null, String(usage.sends)), h('span', null, copy.sends)),
           h('div', { className: 'dshca-stat' }, h('strong', null, String(usage.files)), h('span', null, copy.files)),
           h('div', { className: 'dshca-stat' }, h('strong', null, humanBytes(usage.bytes)), h('span', null, copy.size))),
+        h('div', { className: 'dshca-settings-textpaste' },
+          h('div', { className: 'dshca-settings-textpaste-row' },
+            h('label', { className: 'dshca-settings-textpaste-label' }, copy.textPasteLabel),
+            h('select', {
+              className: 'dshca-settings-select',
+              value: textThresholdState,
+              onChange: e => onTextThresholdChange(e.target.value),
+            }, textThresholdOptions.map(opt => h('option', { key: opt.value, value: opt.value }, opt.label)))),
+          h('div', { className: 'dshca-settings-copy' }, copy.textPasteCopy)),
         h('div', { className: 'dshca-settings-actions' },
           h('button', {
             type: 'button',
@@ -1175,7 +1220,7 @@ window.__ModuleLoader__.load({
       const UPDATE_ID = 'dsh-paste-input';
       const PKG = '@dsh-community/dsh-paste-input';
       const MIRROR = 'lhh010/dsh-paste-input';
-      const PLUGIN_VERSION = '0.1.22';
+      const PLUGIN_VERSION = '0.1.23';
       function semverCmp(a, b) {
         const p = (v) => { const x = v.replace(/^v/, '').split('.').map(n => Number(n) || 0); while (x.length < 3) x.push(0); return x };
         const pa = p(a), pb = p(b);
@@ -1412,6 +1457,53 @@ window.__ModuleLoader__.load({
       };
       ctx.effect(() => inputTriggers.registerSource(source), 'dsh-paste-input: reference codec');
 
+      // Big-text paste interception — CAPTURE phase, so it runs before the
+      // composer's own paste listener (Lexical PASTE_COMMAND on the editor
+      // root; the textarea-era composer inserts via the same event). A pure
+      // text/plain paste landing on the composer that exceeds the threshold
+      // (or TEXT_LINE_LIMIT lines) becomes a paste_text.txt attachment chip
+      // through the same add() pipeline as pasted files: unified naming
+      // family, uniqueLabel (2)/(3) de-dup, upload on send, DSH_PASTE_INPUT_V1
+      // model block, bubble folding. stopPropagation in capture keeps the
+      // event from ever reaching the composer, so the text is not inserted.
+      const onBigTextPaste = event => {
+        if (event.defaultPrevented) return;
+        const clipboardData = event.clipboardData;
+        if (clipboardData === null) return;
+        if (clipboardData.files.length > 0) return; // file paste: existing onPaste owns it
+        const threshold = textThreshold();
+        if (threshold <= 0) return; // feature switched off
+        const text = clipboardData.getData('text/plain');
+        if (text === '') return;
+        if (!(text.length > threshold || text.split('\n').length > TEXT_LINE_LIMIT)) return;
+        // Only intercept pastes landing on the composer itself, never on
+        // unrelated inputs (queue editors, settings search, …).
+        const target = event.target;
+        if (!(target instanceof HTMLElement)) return;
+        if (target instanceof HTMLTextAreaElement) {
+          // Textarea-era composer: its value mirrors the draft (the same
+          // guard onBeforeInput uses to identify the composer).
+          const activeSession = sessions.list?.getSnapshot()?.current;
+          if (activeSession === undefined) return;
+          let mirrorsDraft = false;
+          try { mirrorsDraft = target.value === inputFor(activeSession).state.getSnapshot().draft; } catch { mirrorsDraft = false; }
+          if (!mirrorsDraft) return;
+        } else if (!target.isContentEditable) {
+          return; // Lexical-era composer root is the only contenteditable
+        }
+        event.preventDefault();
+        event.stopPropagation();
+        const sessionId = sessions.list?.getSnapshot()?.current;
+        if (sessionId === undefined) { showToast('请先打开一个会话。'); return; }
+        const file = new File([text], 'paste_text.txt', { type: 'text/plain' });
+        add(sessionId, [{ file, path: 'paste_text.txt' }]).then(
+          () => showToast(`文本较长（${text.length} 字符），已转为 paste_text.txt 附件`),
+          cause => showToast(cause instanceof Error ? cause.message : String(cause)),
+        );
+      };
+      document.addEventListener('paste', onBigTextPaste, true);
+      ctx.effect(() => () => document.removeEventListener('paste', onBigTextPaste, true), 'dsh-paste-input: big text paste listener');
+
       // Global paste interception: clipboard files become attachments; plain
       // text keeps the browser default. First-time paste shows a notice modal.
       const onPaste = event => {
diff --git a/package.json b/package.json
index ab56d94..70fcce5 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@dsh-community/dsh-paste-input",
-  "version": "0.1.22",
-  "description": "DSH WebUI 文件输入增强：Ctrl+V 粘贴（带首次告知弹窗）与拖拽/选择文件，发送时复制进会话工作区临时目录",
+  "version": "0.1.23",
+  "description": "DSH WebUI 文件输入增强：Ctrl+V 粘贴（带首次告知弹窗）、大段纯文本自动转 paste_text.txt 附件、拖拽/选择文件，发送时复制进会话工作区临时目录",
   "type": "module",
   "main": "lib/index.js",
   "exports": {