Feishu / Lark Messaging Skill

You are a messaging specialist for Feishu (飞书, ByteDance's Chinese workplace platform) and Lark (the international version). Your job is to send messages, interactive cards, and marketing content to Feishu/Lark group chats via Custom Bot Webhooks or the App Bot API.

Prerequisites

Check which credentials are available:

echo "FEISHU_WEBHOOK_URL is ${FEISHU_WEBHOOK_URL:+set}"
echo "FEISHU_WEBHOOK_SECRET is ${FEISHU_WEBHOOK_SECRET:+set}"
echo "FEISHU_APP_ID is ${FEISHU_APP_ID:+set}"
echo "FEISHU_APP_SECRET is ${FEISHU_APP_SECRET:+set}"

Two Integration Modes

If no credentials are set, instruct the user:

Custom Bot Webhook (quickest setup):

1. Open a Feishu/Lark group chat
2. Click the group name at the top to open Group Settings
3. Go to Bots > Add Bot > Custom Bot
4. Name the bot and optionally set a Signature Verification secret
5. Copy the webhook URL and add to .env:

   FEISHU_WEBHOOK_URL=https://open.feishu.cn/open-apis/bot/v2/hook/{webhook_id}
   FEISHU_WEBHOOK_SECRET=your_secret_here  # optional, for signed webhooks
   

App Bot API (for advanced use):

1. Go to Feishu Open Platform or Lark Developer Console
2. Create a new app, enable the Bot capability
3. Add required permissions: im:message:send_as_bot, im:chat:readonly
4. Publish and approve the app, then add to .env:

   FEISHU_APP_ID=cli_xxxxx
   FEISHU_APP_SECRET=xxxxx
   

Webhook URL Formats

• Feishu (China): https://open.feishu.cn/open-apis/bot/v2/hook/{webhook_id}
• Lark (International): https://open.larksuite.com/open-apis/bot/v2/hook/{webhook_id}

API Base URLs

• Feishu (China): https://open.feishu.cn/open-apis
• Lark (International): https://open.larksuite.com/open-apis

1. Custom Bot Webhook Messages

1.1 Plain Text Message

curl -s -X POST "${FEISHU_WEBHOOK_URL}" \
  -H "Content-Type: application/json" \
  -d '{
    "msg_type": "text",
    "content": {
      "text": "Hello from OpenClaudia! This is a test message."
    }
  }'

At-mention everyone in the group:

curl -s -X POST "${FEISHU_WEBHOOK_URL}" \
  -H "Content-Type: application/json" \
  -d '{
    "msg_type": "text",
    "content": {
      "text": "<at user_id=\"all\">Everyone</at> Important announcement: new release is live!"
    }
  }'

1.2 Rich Text Message (Post)

Rich text supports bold, links, at-mentions, and images in a structured format.

curl -s -X POST "${FEISHU_WEBHOOK_URL}" \
  -H "Content-Type: application/json" \
  -d '{
    "msg_type": "post",
    "content": {
      "post": {
        "zh_cn": {
          "title": "产品更新公告",
          "content": [
            [
              {"tag": "text", "text": "我们很高兴地宣布 "},
              {"tag": "a", "text": "v2.0 版本", "href": "https://example.com/changelog"},
              {"tag": "text", "text": " 已正式发布！"}
            ],
            [
              {"tag": "text", "text": "主要更新："}
            ],
            [
              {"tag": "text", "text": "1. 全新用户界面\n2. 性能提升 50%\n3. 支持暗色模式"}
            ],
            [
              {"tag": "at", "user_id": "all", "user_name": "所有人"}
            ]
          ]
        }
      }
    }
  }'

English version (for Lark):

curl -s -X POST "${FEISHU_WEBHOOK_URL}" \
  -H "Content-Type: application/json" \
  -d '{
    "msg_type": "post",
    "content": {
      "post": {
        "en_us": {
          "title": "Product Update Announcement",
          "content": [
            [
              {"tag": "text", "text": "We are excited to announce that "},
              {"tag": "a", "text": "v2.0", "href": "https://example.com/changelog"},
              {"tag": "text", "text": " is now live!"}
            ],
            [
              {"tag": "text", "text": "Key updates:"}
            ],
            [
              {"tag": "text", "text": "1. Brand new UI\n2. 50% performance improvement\n3. Dark mode support"}
            ],
            [
              {"tag": "at", "user_id": "all", "user_name": "Everyone"}
            ]
          ]
        }
      }
    }
  }'

Rich Text Tag Reference

1.3 Signed Webhook Requests

If FEISHU_WEBHOOK_SECRET is set, the webhook requires a signature for verification.

Generate a signed request:

# Calculate timestamp and signature
TIMESTAMP=$(date +%s)
STRING_TO_SIGN="${TIMESTAMP}\n${FEISHU_WEBHOOK_SECRET}"
SIGN=$(printf '%b' "${STRING_TO_SIGN}" | openssl dgst -sha256 -hmac "" -binary | openssl base64)

# For proper HMAC-SHA256 signing:
SIGN=$(echo -ne "${TIMESTAMP}\n${FEISHU_WEBHOOK_SECRET}" | openssl dgst -sha256 -hmac "" -binary | base64)

curl -s -X POST "${FEISHU_WEBHOOK_URL}" \
  -H "Content-Type: application/json" \
  -d "{
    \"timestamp\": \"${TIMESTAMP}\",
    \"sign\": \"${SIGN}\",
    \"msg_type\": \"text\",
    \"content\": {
      \"text\": \"Signed message from OpenClaudia.\"
    }
  }"

Feishu signature algorithm details:

1. Concatenate timestamp + "\n" + secret as the string to sign
2. Compute HMAC-SHA256 with an empty key over that string
3. Base64-encode the result
4. Include both timestamp and sign in the request JSON body

2. Interactive Card Messages

Interactive cards are the most powerful message format. They support headers, content sections, images, action buttons, and structured layouts.

2.1 Basic Card Structure

{
  "msg_type": "interactive",
  "card": {
    "header": {
      "title": {
        "tag": "plain_text",
        "content": "Card Title Here"
      },
      "template": "blue"
    },
    "elements": []
  }
}

Header Color Templates

2.2 Card Elements Reference

Markdown Content Block:

{
  "tag": "markdown",
  "content": "**Bold text** and *italic text*\n[Link text](https://example.com)\nList:\n- Item 1\n- Item 2"
}

Divider:

{
  "tag": "hr"
}

Note (small gray footer text):

{
  "tag": "note",
  "elements": [
    {"tag": "plain_text", "content": 
how to use feishu-lark
CursorClaude CodeClineCodexWindsurfGooseGitHub CopilotVS CodeGemini CLIKiloOpencodeKimi CLIRoo ClineAiderContinueZedBolt.newLovablev0Replit AgentSweepSmol DeveloperDevinCavemanAmpAntigravity
How to use feishu-lark on Cursor
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1
Prerequisites
Before installing skills in Cursor, ensure your development environment meets these requirements:
›Cursor installed and configured on your development machine
›Node.js version 16.0+ with npm package manager (verify with node --version)
›Active project directory or workspace where you want to add feishu-lark
2
Execute installation command
Execute the skills CLI command in your project's root directory to begin installation:
$npx skills add https://github.com/openclaudia/openclaudia-skills --skill feishu-larkcopy
The skills CLI fetches feishu-lark from GitHub repository openclaudia/openclaudia-skills and configures it for Cursor.
3
Select Cursor when prompted
The CLI will show a list of available agents. Use arrow keys to navigate and space to select Cursor:
◆ Which agents do you want to install to?
│
│ ── Universal (.agents/skills) ── always included ────
│   • Amp
│   • Antigravity
│   • Cline
│   • Codex
│ ●Cursor(selected)
│   • Cursor
│   • Windsurf
4
Verify installation
Confirm successful installation by checking the skill directory location:
.cursor/skills/feishu-lark
Reload or restart Cursor to activate feishu-lark. Access the skill through slash commands (e.g., /feishu-lark) or your agent's skill management interface.
⚠
Security & Verification Notice
We perform automated surface-level scans (Gen AI Scanner, Socket, Snyk) during installation. These checks detect common vulnerabilities but do not guarantee complete security. Always review skill source code and verify the publisher's reputation before production use.
Skills execute code in your development environment. Always verify the publisher's identity, review recent commits, and test in isolated environments before production deployment.
Additional Resources
›View source code on GitHub›Skills CLI documentation›Learn more about Cursor›What are agent skills?