feishu_reply_message · Lark Cli MCP: Risk & Policy

WHAT IT DOES

What feishu_reply_message does on Lark Cli

AI agents use feishu_reply_message to create or update resources in Lark Cli — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Lark Cli environment.

WHY IT NEEDS A POLICY

Why feishu_reply_message needs a policy

This tool creates a new reply message in a conversation or thread, which is a reversible write operation. It does not delete or overwrite existing data, nor does it execute code or involve financial transactions. Misuse could expose sensitive information or impersonate the user in conversations.

From the tool's definition 回复某条飞书消息（支持线程回复） — 'reply' to a Feishu message, including thread replies

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

feishu_reply_message Rate-limited

feishu_reply_message stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "feishu_reply_message": {
      "limits": [
        {
          "counter": "feishu_reply_message_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Lark Cli, so you can run agents against it safely.

FAQ

Questions about feishu_reply_message

What does the feishu_reply_message tool do? +

回复某条飞书消息（支持线程回复）. It is categorised as a Write tool in the Lark Cli MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on feishu_reply_message? +

Register the Lark Cli MCP server in PolicyLayer and add a rule for feishu_reply_message: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Lark Cli. Nothing to install.

What risk level is feishu_reply_message? +

feishu_reply_message is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit feishu_reply_message? +

Yes. Add a rate_limit block to the feishu_reply_message rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block feishu_reply_message completely? +

Set action: deny in the PolicyLayer policy for feishu_reply_message. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides feishu_reply_message? +

feishu_reply_message is provided by the Lark Cli MCP server (yoreland/lark-cli-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.