mcp-whatsapp

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

Annotations indicate this is a destructive, non-idempotent, open-world operation, which the description does not contradict. The description adds valuable context beyond annotations by explaining the synthesis behavior when vcard is omitted and specifying the vCard 3.0 standard, enhancing transparency about how the tool functions in practice.

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 extremely concise and front-loaded, consisting of only two sentences that efficiently convey the core functionality and key behavioral detail. Every sentence earns its place without any wasted words, making it easy to parse quickly.

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?

Given the destructive nature indicated by annotations and the lack of an output schema, the description is reasonably complete for a tool with clear parameters and annotations. It explains the main behavior (synthesis) but could benefit from mentioning potential side effects or error conditions, though the annotations provide some safety context.

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?

With 100% schema description coverage, the input schema already documents all parameters thoroughly. The description adds minimal semantic value by mentioning the synthesis logic for vcard omission, but it does not provide significant additional meaning beyond what the schema descriptions already cover.

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 specific action ('Send a contact card') and distinguishes it from sibling tools like send_message or send_file by focusing on contact card transmission. It also explains the unique behavior of synthesizing a vCard when vcard is omitted, which further differentiates its purpose.

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 provides clear context on when to use this tool—specifically for sending contact cards, with guidance on parameter usage (vcard omission triggers synthesis). However, it does not explicitly state when not to use it or name alternatives among sibling tools, such as send_message for text-based communication.

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