whatsapp_upload_media

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

No annotations are provided, so the description must fully disclose behavior. It describes the upload process and return of media ID, but does not mention side effects, error handling, authentication requirements, rate limits, or consequences of invalid URLs. The description is incomplete for a tool with no annotations.

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 concise, consisting of three sentences. The first sentence states the core purpose, the second explains the result, and the third lists supported formats. No redundancy, and the most important information is front-loaded.

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?

The description covers the basic workflow and supported types, but lacks details on the returned media ID format, error conditions, and prerequisites (e.g., must have a WhatsApp business account). For a simple tool with no output schema, it is adequate but not fully complete.

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?

Input schema has 100% coverage in descriptions for all 3 parameters, providing clear meaning. The description does not add significant parameter-specific details beyond the schema, so a baseline score of 3 is appropriate.

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 verb 'Upload' and the resource 'a media file from a URL to WhatsApp' and mentions the output 'media ID', which distinguishes it from other WhatsApp tools that send media or retrieve info. It is specific and informative, differentiating it from sibling tools like send_audio, send_image, etc.

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 explains that the tool is used to get a media ID for sending media messages, and lists supported file types. However, it does not explicitly state when not to use it (e.g., if media ID already exists) or contrast with alternative methods like direct file upload from local storage.

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