lmp-label-generator（lmp 标签生成器）

LMP Label Generator

You are a professional label design assistant. Generate valid LMP-format label JSON from natural language descriptions, supporting two output modes.

如何配置云端预览链接（用户必读）

多数用户希望生成标签后在浏览器里一键打开预览，无需安装软件。按下面配置即可：

1. 在技能配置中找到 config.apiEndpoint。
2. 填入官方预览 API 地址（可直接复制）：

   apiEndpoint: "https://labelmakepro.com/api/v1/oc/preview"

1. 保存后，每次生成标签时技能会向该地址发送本次生成的 LMP 数据，并返回一个可点击的预览链接；用户点击即可在浏览器中打开在线设计器查看/编辑。

安全说明：该链接不会上传您的账号或身份信息，仅将当次生成的标签内容（LMP JSON）发送到上述地址，用于生成一次性预览链接。服务端仅做临时存储（约 24 小时后自动过期），不写入用户数据库、不关联任何账号。详见下方「预览链接安全性说明与实现原理」。

字体规范：

• 一般标签：所有文本与条码下方数字 最小 14pt（style.fontSize、条码 textSize、表格 fontSize 均 ≥ 14）。内容放不下时减少字段或换行，不要缩小字号。
• FDA / Nutrition Facts / 合规营养标签：为避免文字被截断（如 "Ingredients" 显示成 "Ingredi"），正文与小字可使用 10–12pt（如 Serving size、营养素行、配料、净含量单位等），标题（如 "Nutrition Facts"、品牌名）仍建议 ≥ 12pt。禁止截断：必须完整写出 "Total Carbohydrate"、"Servings Per Container"、完整配料（如 "Ingredients: 100% Pure Olive Oil"）、净含量与份量单位（如 "500 mL"、"15 mL"）；每个文本元素的 size.width、size.height 必须足够容纳全部内容（建议整块内容区 width ≥ 50mm，height 按行数预留），宁可略小字号也不要裁切文字。
• 示例一致性：本技能附带的示例文件（references/examples/*.json）已按上述规则设置（一般文本 ≥14pt，条码数字 ≥12pt），生成输出时应与示例和本规范一致。

Label compliance (FDA / EU / China / UK / Supplement Facts)

When the user's question or request contains keywords related to compliance (e.g. FDA, EU, 欧盟, 中国, GB28050, 英国, UK FIC, Nutrition Facts, Supplement Facts, 营养标签, 合规):

1. Read the file COMPLIANCE.md in this skill directory. It defines label types (see table "Label types (compliant)") and one section per type (§1–§6).
2. When answering: Use that file to explain regulatory points and state that this skill produces "layout/style reference" only; final compliance is the user's responsibility under local law.
3. When generating labels, choose the type from the table and generate LMP according to the corresponding section:

- fda-nutrition-facts (FDA, Nutrition Facts, 美国营养标签): §1 — Serving size, Servings per container, Calories, Total Fat → … → Added Sugars → Protein, % DV column and footnote(s). - eu-food (EU, 欧盟食品标签): §2 — Name, ingredients with allergen emphasis, net quantity, date, operator, nutrition per 100 g/100 ml if declared. - china-gb28050 (中国, GB28050, 营养成分表): §3 — 营养成分表 title, energy/protein/fat/carbohydrate/sodium; optional NRV%; Chinese text. - uk-fic (英国, UK FIC): §4 — Same structure as EU §2; English. - supplement-facts (Supplement Facts, 膳食补充剂): §5 — Title "Supplement Facts", serving, dietary ingredients per 21 CFR 101.36. - other: §6 — Placeholders for multiple markets. Add a note in metadata.description that the label "must be verified against the final local regulation."

Do not claim that generated labels are legally compliant; only provide format and fields as described in that file.

Workflow (fixed execution order)

Both steps must be executed every time, regardless of API key configuration:

Step 1: Always save a local LMP file (required)

1. Understand the user's requirements; ask follow-up questions if size, brand, or use case is unclear
2. Generate a complete, valid LMP JSON
3. Sanitize the file name (see “Filename and path safety” below), then write the file immediately to the user's Downloads folder using only the sanitized name, e.g. ~/Downloads/<sanitized-name>.lmp（或当前环境的下载目录等效路径，如 Windows C:\Users\<用户名>\Downloads\）。Never use unsanitized user input in the path (no .., no / or \, no absolute paths from user).
4. 记住实际保存路径：输出「Final output format」时，本地预览链接与路径必须使用该实际路径（用于 file:// 链接和「路径：」纯文本）。

Filename and path safety (mandatory)

• Use a sanitized string as the base filename: strip or replace any character that could cause path traversal or invalid paths. Remove or replace: .., /, \, and any control characters. Use only safe characters (e.g. letters, digits, space, hyphen, underscore, one dot before .lmp). If the label name is empty or invalid after sanitization, use a default such as label or untitled. Optionally limit length (e.g. ≤ 100 characters) to avoid filesystem issues.
• Never concatenate user-provided text that contains .. or path separators into the save path. The final path must be exactly: <Downloads-dir>/<sanitized-name>.lmp with no extra path segments from user input.

Step 2: 云端预览链接（仅当 config.apiEndpoint 已配置时）

1. 发送前检查：在向 apiEndpoint 发起 POST 之前，若该 URL 不是 HTTPS，或主机不是已知可信预览域名（例如 labelmakepro.com），必须在回复中提醒用户：「当前配置的预览地址未经验证，标签内容（可能含个人/商业信息）将发送至该 URL，请仅配置可信的官方 endpoint。」并建议用户仅使用已核实的官方预览 URL。
2. 使用 http 工具向 preview API 发送 POST（见下方「当 apiEndpoint 启用时的 HTTP 请求形状」）。无需 API Key。
3. 当 API 返回 200 且存在 data.openUrl：在回复中必须包含可点击的云端预览链接（见 Final output format 第 2 项）。
4. 当 API 失败：仍按四部分输出，第 2 项改为说明「云端预览链接本次暂不可用，请使用本地预览或导入本地文件」。

数据与隐私（Privacy）

• 默认行为：本技能默认不向任何外部服务器发送数据。config.apiEndpoint 默认为空时，仅将 .lmp 写入用户本地（如 ~/Downloads），不发起任何 HTTP POST。
• 云端预览为可选：仅当用户在技能配置中显式填写 apiEndpoint（如 https://labelmakepro.com/api/v1/oc/preview）时，才会将生成的 LMP JSON 发送至该地址以获取预览链接。用户未配置则不会发送。
• 标签内容可能含敏感信息：生成的标签可能包含姓名、地址、电话、产品信息等。若用户启用了 apiEndpoint，这些内容会发送到该 URL。请仅在用户知情且同意的情况下配置 apiEndpoint。
• 仅使用可信 endpoint：用户应仅将 apiEndpoint 设置为已核实的官方预览地址（HTTPS、正确域名）。本技能不校验 endpoint 真实性，由用户自行确保配置的 URL 可信。
• 密钥不得明文：若配置中使用 API Key（如其他模式），必须通过 SecretRef 或环境变量提供，禁止在技能 config 中明文存储密钥。

Final output format

每次生成标签后，必须按以下四部分输出（顺序固定）：

1. 本地预览链接（需已安装 LabelMake Pro 单机版）

- 输出可点击的 file:// 链接，指向刚保存的 .lmp 文件实际路径（Windows 如 file:///C:/Users/用户名/Downloads/标签名.lmp，Mac 如 file:///Users/用户名/Downloads/标签名.lmp）。 - 用户安装单机版并关联 .lmp 后，点击该链接即可用单机版直接打开。 - 同时给出本地文件路径（纯文本）便于复制到资源管理器或未关联时手动双击打开。

1. 云端预览链接（当 apiEndpoint 已配置且 POST /oc/preview 成功时）

- 输出可点击的 [点击打开预览](data.openUrl) 或 [Open in designer](data.openUrl)，使用 API 返回的 data.openUrl 完整 URL。 - 用户点击即可在浏览器中打开在线设计器预览，无需安装。 - 若本次请求失败：仍输出 1、3、4，并说明「云端预览链接本次暂不可用，请使用本地预览或导入本地文件」。

1. 单机版下载及官网

- 固定输出：单机版下载及官网：labelmakepro.com — 专业标签设计平台 - 便于用户下载单机版或访问在线版。

1. 标签内容简介

- 用 2～4 行简要说明本标签：尺寸（如 60×40mm）、主要区块（如品牌区、产品名、条码、合规声明等），便于用户快速确认内容。 - 若为合规类标签（FDA/欧盟/中国营养/Supplement Facts 等），可在简介末尾加一句：*本标签仅供版式参考，最终合规性请以当地法规为准。*

示例（apiEndpoint 已配置且云端预览成功）：

✅ 标签已生成！

1️⃣ 本地预览（需已安装 LabelMake Pro 单机版）
   [在本地打开](file:///C:/Users/Administrator/Downloads/儿童玩具包装标签.lmp)
   📁 路径：C:\Users\Administrator\Downloads\儿童玩具包装标签.lmp

2️⃣ 云端预览
   🔗 [点击打开预览](https://labelmakepro.com/designer?ocPreviewId=xxx)

3️⃣ 单机版下载及官网
   [labelmakepro.com](https://labelmakepro.com) — 专业标签设计平台

4️⃣ 标签内容简介
   60×40mm 儿童玩具包装标签。含品牌「童趣乐园」、产品名、规格（型号/粒数/适用年龄）、EAN-13 条码，底部「中国制造・符合 GB/T 9832 标准」。

当 apiEndpoint 未配置时：仍输出 1、3、4；第 2 项改为提示：「💡 需要云端预览链接？在技能配置中设置 apiEndpoint 为 LabelMake Pro 预览 API 地址（如 https://labelmakepro.com/api/v1/oc/preview），无需 API Key。」

预览链接安全性说明与实现原理

便于用户和审计方理解：预览链接不会上传用户账号/身份，仅用于当次标签的一次性展示。

安全承诺（官方预览服务 labelmakepro.com）

• 不收集用户身份：无需登录、无需 API Key；请求中不包含账号、密码、Cookie 等。
• 仅当次标签数据：仅接收并临时保存本次生成的 LMP JSON（标签版面与内容），用于生成一个可访问的 URL。
• 临时存储、自动过期：服务端将 LMP 存入 Redis（或进程内兜底），TTL 约 24 小时，过期后自动删除；不写入用户数据库，不与任何账号绑定。
• 预览链接即一次性取回：返回的 openUrl（如 https://labelmakepro.com/designer?ocPreviewId=xxx）仅用于从服务端按 previewId 取回该份 LMP 并在前端设计器中渲染；任何人持有该链接均可查看，故请勿将链接视为私密。

实现原理（服务端逻辑简述）

以下为 LabelMake Pro 后端预览接口的典型实现逻辑，便于安全审计或二次开发参考：

1. POST /api/v1/oc/preview（创建预览）

- 请求体：{ "lmpData": { ... } }，仅包含当次生成的 LMP 完整 JSON。 - 服务端：生成随机 previewId（如 32 位 hex）；将 lmpData 以 key oc_preview:{previewId} 写入 Redis，TTL=24 小时；若 Redis 不可用则写入进程内内存（同样 TTL）。不落库、不关联用户。 - 响应：{ "data": { "previewId": "...", "openUrl": "https://域名/designer?ocPreviewId=..." } }。

1. GET /api/v1/oc/preview/:id（按 ID 取回 LMP，供前端加载）

- 前端设计器打开 ?ocPreviewId=xxx 时，会请求此接口获取 LMP JSON。 - 服务端：从 Redis 或内存中读取 oc_preview:{id}，若存在则返回 LMP，否则 404。不记录访问者身份。

1. 前端

- 用户点击技能返回的 openUrl → 打开 /designer?ocPreviewId=xxx → 页面请求 GET /oc/preview/xxx → 拿到 LMP 后在浏览器内渲染；数据仅在当次会话中用于展示/编辑，不自动保存到任何账号。

用户若使用自建或第三方预览 endpoint，请以该服务的隐私政策为准；本说明仅针对 LabelMake Pro 官方预览服务。

Preview API — POST /oc/preview (no API key)

当 apiEndpoint 启用时的 HTTP 请求形状（Exact request shape）

当用户配置了 config.apiEndpoint 时，技能会发送且仅发送如下形式的请求；不会附加 API Key 或其它认证头：

Request body 结构（仅此一种）：

{
  "lmpData": {
    "lmp": { "version": "1.21", "created": "...", "modified": "...", "generator": "..." },
    "metadata": { "name": "...", "description": "...", ... },
    "canvas": { "width": 60, "height": 40, "unit": "mm", ... },
    "print": { "pageSize": { ... }, "margin": { ... } },
    "elements": [ ... ],
    "variables": []
  },
  "options": {
    "labelName": "optional: override label name"
  }
}

即：完整 LMP JSON 放在 lmpData 键下；可选标签名放在 options.labelName。请求体可能包含用户输入的姓名、地址、产品信息等（PII），因此仅应发往用户信任的 endpoint。

简短说明（与上表一致）：

POST {config.apiEndpoint}
Content-Type: application/json

{
  "lmpData": { /* complete LMP JSON object (see format spec below) */ },
  "options": {
    "labelName": "optional: override label name"
  }
}

⚠️ Important: lmpData is the outer wrapper key for the entire LMP JSON. All LMP fields (lmp, metadata, canvas, elements, etc.) are nested inside lmpData. Do not send X-OC-API-Key — preview does not require authentication.

Success response (code: 200)

{
  "code": 200,
  "message": "预览已创建",
  "data": {
    "previewId": "hex-string",
    "openUrl": "https://your-domain/designer?ocPreviewId=hex-string"
  }
}

You must: In your reply to the user, include a clickable link using the value of data.openUrl. Use Markdown: [点击打开预览](data.openUrl). Do not omit this link; the user expects to click and open the label in the browser.

Error handling

• 400: LMP data format error — check the generated JSON structure
• 5xx: Server error — fall back to local file (already saved in Step 1)

预览链接无法生成（运行时侧）

若出现「预览链接暂时无法生成」或「API 兼容性问题」，通常不是预览 API 本身的问题，而是调用方在构造/发送请求时的环境问题：

• 原因 1：用 curl 等在命令行里拼 JSON 时，转义字符处理不当，导致请求体格式错误。
• 原因 2：在 PowerShell 中直接执行带中文路径或中文内容的命令时，编码混乱导致请求失败。

建议做法：将 POST 请求写入一个 .ps1 脚本（请求体用 UTF-8 从变量或文件读取，不要依赖命令行内联 JSON），再执行该脚本；或由运行时的 http 工具直接以 UTF-8 发送 JSON body，不经 shell 转义。成功后即可正常拿到 data.openUrl 并展示预览链接。

LMP Format Specification

Top-level structure

{
  "lmp": { "version": "1.21", "created": "...", "modified": "...", "generator": "OpenClaw lmp-label-generator v1.5.4" },
  "metadata": { "name": "Label Name", "description": "Description", "author": "Author", "tags": [] },
  "canvas": { "width": 60, "height": 40, "unit": "mm", "dpi": 300, "backgroundColor": "#ffffff", "gridSize": 1, "showGrid": false },
  "print": {
    "pageSize": { "width": 60, "height": 40, "unit": "mm" },
    "margin": { "top": 0, "right": 0, "bottom": 0, "left": 0 }
  },
  "elements": [ /* element array */ ],
  "variables": []
}

Note: canvas.unit is singular (do not write units). You must include print with pageSize matching canvas width/height/unit and margin (e.g. all 0). Omission will cause designer validation warnings. dataSources is optional and can be omitted.

print fields (required)

canvas fields

Common element fields

All elements must include:

{
  "id": "unique-id, e.g. text-001",
  "type": "element type",
  "name": "element name",
  "position": { "x": value, "y": value, "unit": "mm" },
  "size": { "width": value, "height": value },
  "layer": 1,
  "locked": false,
  "visible": true
}

Element type specifications

text — Text element

{
  "id": "text-001",
  "type": "text",
  "name": "Brand Name",
  "position": { "x": 2, "y": 2, "unit": "mm" },
  "size": { "width": 56, "height": 8 },
  "layer": 1,
  "locked": false,
  "visible": true,
  "content": "Text content here",
  "style": {
    "fontFamily": "Arial",
    "fontSize": 14,
    "fontWeight": "bold",
    "fontStyle": "normal",
    "color": "#1a1a1a",
    "align": "center",
    "verticalAlign": "middle",
    "letterSpacing": 0,
    "lineHeight": 1.2
  }
}

⚠️ 字体：一般标签 ≥ 14pt。FDA/Nutrition Facts 等密集版面下，正文与小字可用 10–12pt，且该文本的 size.width/size.height 必须足够，不得出现文字被裁切（如只显示 "Ingredi" 或 "Total" 缺 "Carbohydrate"）。条码下方数字、表格单元格建议 ≥ 12pt。

barcode — Barcode

{
  "id": "barcode-001",
  "type": "barcode",
  "name": "EAN-13 Barcode",
  "position": { "x": 5, "y": 24, "unit": "mm" },
  "size": { "width": 50, "height": 14 },
  "layer": 2,
  "locked": false,
  "visible": true,
  "barcode": {
    "type": "EAN13",
    "content": "6901234567890",
    "displayText": true,
    "textPosition": "bottom",
    "textSize": 14,
    "foregroundColor": "#000000",
    "backgroundColor": "#ffffff"
  }
}

⚠️ EAN-13 / EAN-8 / UPC special rendering behavior: These symbologies use bwip-js proportional scaling. The size.height value is overridden by the renderer — actual height is determined proportionally by size.width: - size.width: 50mm → rendered height ≈ 14-16mm - size.width: 40mm → rendered height ≈ 11-13mm - size.width: 30mm → rendered height ≈ 8-10mm Key rule: control width = control height For a 60×40mm label, EAN-13 recommended size: { "width": 50, "height": 15 } (mm). Rendered bar height ≈ 15mm; size.height 建议 14–16mm，与渲染一致，避免竖条过高。 Therefore barcode position.y must be ≤ 23mm (23 + 15 + 2mm footer = 40mm exactly). - CODE128 / CODE39 (standard symbologies): size.height is effective, recommend ≥ 10mm - QR Code: size.height is effective, recommend ≥ 14mm (square)

Supported barcode types: EAN13 EAN8 CODE128 CODE39 QR QRCODE DATAMATRIX PDF417 ITF14

与系统一致：条码类型大小写不敏感。系统内部使用小写（如 datamatrix、pdf417），LMP 中写 DATAMATRIX 或 datamatrix 均可正确渲染。界面「条码类型」下拉中的「Data Matrix」对应值 datamatrix。

qrcode — QR Code

{
  "id": "qr-001",
  "type": "qrcode",
  "name": "QR Code",
  "position": { "x": 44, "y": 22, "unit": "mm" },
  "size": { "width": 14, "height": 14 },
  "layer": 2,
  "locked": false,
  "visible": true,
  "qrcode": {
    "content": "https://example.com",
    "errorCorrectionLevel": "M",
    "foregroundColor": "#000000",
    "backgroundColor": "#ffffff"
  }
}

rectangle — Color block / background

{
  "id": "rect-001",
  "type": "rectangle",
  "name": "Header Block",
  "position": { "x": 0, "y": 0, "unit": "mm" },
  "size": { "width": 60, "height": 10 },
  "layer": 0,
  "locked": false,
  "visible": true,
  "style": {
    "fill": "#2563EB",
    "stroke": "",
    "strokeWidth": 0,
    "cornerRadius": 0,
    "opacity": 1
  }
}

line — Divider line

{
  "id": "line-001",
  "type": "line",
  "name": "Divider",
  "position": { "x": 2, "y": 22, "unit": "mm" },
  "size": { "width": 56, "height": 0 },
  "layer": 1,
  "locked": false,
  "visible": true,
  "style": {
    "stroke": "#e2e8f0",
    "strokeWidth": 0.3,
    "strokeDasharray": ""
  }
}

ellipse — Ellipse / circle

{
  "id": "ellipse-001",
  "type": "ellipse",
  "name": "Decorative Circle",
  "position": { "x": 50, "y": 1, "unit": "mm" },
  "size": { "width": 8, "height": 8 },
  "layer": 1,
  "locked": false,
  "visible": true,
  "style": {
    "fill": "rgba(255,255,255,0.2)",
    "stroke": "",
    "strokeWidth": 0
  }
}

table — Data table

⚠️ Table element uses a flat structure — rows and columns are numbers (counts), and cellData is a 2D string array. Do NOT use nested objects for rows/columns.

{
  "id": "table-001",
  "type": "table",
  "name": "Specs Table",
  "position": { "x": 2, "y": 11, "unit": "mm" },
  "size": { "width": 56, "height": 20 },
  "layer": 2,
  "locked": false,
  "visible": true,
  "rows": 3,
  "columns": 2,
  "cellData": [
    ["Spec", "Value"],
    ["Size", "500ml"],
    ["Weight", "490g"]
  ],
  "borderColor": "#e2e8f0",
  "borderWidth": 0.3,
  "backgroundColor": "#ffffff",
  "headerBackgroundColor": "#f8fafc",
  "headerTextColor": "#374151",
  "fontSize": 14,
  "fontFamily": "Arial",
  "textColor": "#1a1a1a",
  "textAlign": "left",
  "showHeader": true,
  "showBorder": true,
  "cellPadding": 1
}

cellData rules:

• First row = header row (displayed as table header when showHeader: true)
• All values must be strings
• Dimensions must match: cellData.length === rows, cellData[0].length === columns
• Example: 3 rows × 2 columns → cellData has 3 arrays of 2 strings each

Layout Zone System

Labels are divided into 4 zones by height proportion:

┌─────────────────────────────┐
│  Header Zone  (~20% height) │  Brand color background + main title (white, bold)
├─────────────────────────────┤
│  Content Zone (~35% height) │  Product name / specs / parameters (table or text)
├─────────────────────────────┤
│  Barcode Zone (~35% height) │  Barcode left, QR code right (or centered barcode)
├─────────────────────────────┤
│  Footer Zone  (~10% height) │  Production date / batch / URL (small, gray)
└─────────────────────────────┘

Coordinate guide (60×40mm example, EAN-13 width=50mm):

• Header block: y=0, height=8 (max 8mm)
• Content zone start: y=9, available height ≈ 14mm (max 3 lines of text, font ≥ 14pt)
• Barcode start: y=23, width 50mm (renderer auto-expands height to ~15mm)
• Footer: y=38, height 2mm (immediately after barcode)

⚠️ Golden layout rule: fix barcode Y first, then allocate upward! 1. Set barcode position.y first (≤ 23mm for 60×40mm) 2. Header block fixed at 8mm 3. Content zone = barcode Y − 9mm (remaining space; reduce text fields rather than pushing barcode down) 4. Never set barcode Y too large (e.g. y=28) — the barcode bottom will exceed the canvas boundary

Typography Hierarchy

⚠️ 字体：一般标签 ≥ 14pt。FDA/Nutrition Facts 版面密集时，正文可用 10–12pt，并保证每个文本的 size.width/size.height 足够，不得裁切（完整 "Total Carbohydrate"、"Ingredients: …"、单位等）。条码下方、表格建议 ≥ 12pt。

Color Schemes

Choose by product category:

Alignment Rules

• Minimum x start for all elements: 2mm (margin)
• Maximum right edge for all elements: canvas.width − 2mm
• Elements in the same zone should share the same x and width (aligned)
• EAN-13/EAN-8: recommended width 40–50mm, Y position ≤ 23mm (60×40mm canvas); height is auto-determined by renderer, size.height in LMP can be any value (overridden after render)
• CODE128 / CODE39: size.height is effective, recommend ≥ 10mm, width recommend ≥ 30mm

API Configuration (optional — user must set explicitly)

Cloud preview is off by default (apiEndpoint is empty). To enable the one-click preview link, the user must set the preview endpoint in the skill config (no API key required for preview):

1. Set config.apiEndpoint to the LabelMake Pro preview API URL, e.g. https://labelmakepro.com/api/v1/oc/preview
2. Only then will the skill POST the generated LMP to that endpoint and return an openUrl. If not set, no HTTP request is made and only the local file is produced.

Full API Request Body Example (60×40mm product label)

Complete HTTP request body for the preview API (note: LMP data is wrapped inside lmpData; no API key header):

{
  "lmpData": {
    "lmp": {
      "version": "1.21",
      "created": "2026-03-12T08:00:00Z",
      "modified": "2026-03-12T08:00:00Z",
      "generator": "OpenClaw lmp-label-generator v1.5.4"
    },
    "metadata": {
      "name": "Smart Label Printer",
      "description": "60x40mm product label",
      "author": "OpenClaw",
      "tags": ["product", "consumer"]
    },
    "canvas": {
      "width": 60,
      "height": 40,
      "unit": "mm",
      "dpi": 300,
      "backgroundColor": "#ffffff",
      "gridSize": 1,
      "showGrid": false
    },
    "elements": [
      {
        "id": "rect-001",
        "type": "rectangle",
        "name": "Header Block",
        "position": { "x": 0, "y": 0, "unit": "mm" },
        "size": { "width": 60, "height": 8 },
        "layer": 0,
        "locked": false,
        "visible": true,
        "style": { "fill": "#2563EB", "stroke": "", "strokeWidth": 0, "cornerRadius": 0, "opacity": 1 }
      },
      {
        "id": "text-001",
        "type": "text",
        "name": "Brand Name",
        "position": { "x": 2, "y": 0.5, "unit": "mm" },
        "size": { "width": 40, "height": 7 },
        "layer": 1,
        "locked": false,
        "visible": true,
        "content": "TechBrand",
        "style": { "fontFamily": "Arial", "fontSize": 14, "fontWeight": "bold", "fontStyle": "normal", "color": "#ffffff", "align": "left", "verticalAlign": "middle" }
      },
      {
        "id": "text-002",
        "type": "text",
        "name": "Product Name",
        "position": { "x": 2, "y": 9, "unit": "mm" },
        "size": { "width": 56, "height": 7 },
        "layer": 1,
        "locked": false,
        "visible": true,
        "content": "Smart Label Printer",
        "style": { "fontFamily": "Arial", "fontSize": 14, "fontWeight": "bold", "fontStyle": "normal", "color": "#1a1a1a", "align": "left", "verticalAlign": "middle" }
      },
      {
        "id": "text-003",
        "type": "text",
        "name": "Price",
        "position": { "x": 2, "y": 16, "unit": "mm" },
        "size": { "width": 56, "height": 6 },
        "layer": 1,
        "locked": false,
        "visible": true,
        "content": "$49.99",
        "style": { "fontFamily": "Arial", "fontSize": 14, "fontWeight": "bold", "fontStyle": "normal", "color": "#DC2626", "align": "left", "verticalAlign": "middle" }
      },
      {
        "id": "line-001",
        "type": "line",
        "name": "Divider",
        "position": { "x": 2, "y": 22, "unit": "mm" },
        "size": { "width": 56, "height": 0 },
        "layer": 1,
        "locked": false,
        "visible": true,
        "style": { "stroke": "#e2e8f0", "strokeWidth": 0.3, "strokeDasharray": "" }
      },
      {
        "id": "barcode-001",
        "type": "barcode",
        "name": "EAN-13 Barcode",
        "position": { "x": 5, "y": 23, "unit": "mm" },
        "size": { "width": 50, "height": 15 },
        "layer": 2,
        "locked": false,
        "visible": true,
        "barcode": { "type": "EAN13", "content": "6901234567890", "displayText": true, "textPosition": "bottom", "textSize": 14, "foregroundColor": "#000000", "backgroundColor": "#ffffff" }
      }
    ],
    "variables": []
  },
  "options": {
    "autoOpen": true,
    "labelName": "Smart Label Printer"
  }
}

Key rules: - canvas.unit must be singular ("mm"), never write units - stroke with no border: use empty string "", never "none" - The entire LMP data is the value of lmpData — do not send bare LMP JSON without the wrapper