whatsapp-mcp-server

whatsapp_send_image

Send an image to a WhatsApp contact by providing a publicly accessible URL. Optionally add a caption or reply to a specific message.

Instructions

Send an image message to a WhatsApp phone number. Provide a publicly accessible image URL.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "to": "<to>",
      "image_url": "<image_url>"
    },
    "name": "whatsapp_send_image"
  }
}

Input Schema

Name	Required	Description
`to`	Yes	Phone number in E.164 format, e.g. +15551234567
`caption`	No	Optional caption (max 1024 characters)
`image_url`	Yes	Publicly accessible URL of the image
`reply_to_message_id`	No	Message ID to reply to

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.1.0Jun 26, 2026

TDQS

B3.4/5.0

Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, and the description only states the action and URL requirement. It does not disclose potential failures (e.g., invalid URL), authentication needs, rate limits, or whether it is destructive. The description carries the full burden but is minimal.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two concise sentences, front-loaded with the action, and provides all essential information without waste.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the lack of output schema and the tool's complexity (4 parameters), the description does not hint at what the response contains (e.g., message ID, success status). The agent would need additional knowledge to handle the result. This leaves a completeness gap.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the baseline is 3. The description adds no additional meaning beyond the schema—it merely reiterates the 'publicly accessible image URL' which is already in the schema. No extra semantics.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb 'send' and resource 'image message to a WhatsApp phone number', and specifies the requirement for a publicly accessible image URL. This distinguishes it from sibling tools like whatsapp_send_text or whatsapp_send_document.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies when to use this tool (to send an image message) but provides no explicit guidance on when not to use it or alternatives like whatsapp_send_text for text messages. The context is clear but lacks exclusions.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Deploy Server