wa_send_image_message

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

No annotations are provided, so the description carries full responsibility. It mentions the public URL requirement but does not disclose potential side effects, authorization needs, irreversibility of sending a message, or error conditions. The tool appears to create a message, but this behavioral impact is not described.

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

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

The description is a single concise sentence that is front-loaded with the primary purpose. Every word contributes meaning, with no redundancy or filler.

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

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

Despite having 5 parameters, no annotations, and no output schema, the description contains only a minimal statement of intent. It does not explain required parameters, behavior, or return values, making it incomplete for an agent to invoke correctly.

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

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

Schema coverage is 0% and the description only clarifies the image_url parameter ('from a public URL'). It does not explain phone_number_id, to, caption, or confirm, leaving these parameters semantically underdocumented for an agent.

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

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

The description clearly states the action ('Send an image'), the resource ('image'), and the channel ('via WhatsApp'), with the important constraint that the image comes from a public URL. This distinguishes it from sibling tools like wa_send_text_message and wa_send_template_message by message type.

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

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

The description gives no guidance on when to use this tool versus alternatives such as wa_send_text_message or wa_send_template_message. It implies usage for sending images but provides no explicit context, exclusions, or alternative recommendations.

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