upload_image · WeChat Official Account MCP Server MCP

WHAT IT DOES

What upload_image does on WeChat Official Account MCP Server

AI agents use upload_image to create or update resources in WeChat Official Account MCP Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your WeChat Official Account MCP Server environment.

WHY IT NEEDS A POLICY

Why upload_image needs a policy

Uploading images to a WeChat Official Account is a reversible modification operation that creates new media assets (media_id entries). This falls under the Write category.

From the tool's definition Tool description indicates 'upload_image' performs an upload operation to WeChat Official Account to obtain a media_id.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

upload_image Rate-limited

upload_image 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": {
    "upload_image": {
      "limits": [
        {
          "counter": "upload_image_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 WeChat Official Account MCP Server, so you can run agents against it safely.

FAQ

Questions about upload_image

What does the upload_image tool do? +

上传图片到微信公众号获取media_id. It is categorised as a Write tool in the WeChat Official Account MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on upload_image? +

Register the WeChat Official Account MCP Server MCP server in PolicyLayer and add a rule for upload_image: 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 WeChat Official Account MCP Server. Nothing to install.

What risk level is upload_image? +

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

Can I rate-limit upload_image? +

Yes. Add a rate_limit block to the upload_image 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 upload_image completely? +

Set action: deny in the PolicyLayer policy for upload_image. 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 upload_image? +

upload_image is provided by the WeChat Official Account MCP Server MCP server (jungley8/mcp4agent). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.