send_file

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

With no annotations, the description carries the full burden and does disclose supported media types, recipient formats, absolute-path requirement, and a return shape. Still, it omits important send-side behavior such as authentication needs, file size limits, rate limits, and failure handling.

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 front-loaded and organized with Args and Returns sections. The Returns section is somewhat redundant because an output schema exists, and the recipient explanation is a bit verbose, but there is little waste.

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?

For a simple two-parameter send tool with an output schema, the description gives enough parameter detail to invoke it correctly. The main remaining gap is behavioral context around authentication, limits, and failure modes, which is not covered by annotations.

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 description coverage is 0%, so the description must compensate, and it does: recipient is explained as either a country-code phone number without symbols or a JID with examples, and media_path is described as an absolute path with supported file categories.

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 states a clear verb and resource: sending a file via WhatsApp, with supported media types listed. It does not explicitly distinguish this tool from the sibling send_audio_message, even though audio is mentioned, so it falls short of full sibling differentiation.

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?

It gives a concrete recipient rule for group messages: use the JID. However, it does not say when to use send_file rather than send_message or send_audio_message, nor does it state any exclusions or prerequisites.

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