initiate_call

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states the action ('Initiate WhatsApp call') but does not disclose behavioral traits such as required permissions, call state handling, failure modes, or side effects. This is slightly more informative than a tautology but still lacks meaningful transparency.

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 highly concise, consisting of a single front-loaded sentence that immediately states the purpose. It is efficient and easy to parse. However, it may be too brief, omitting necessary context, but for what it includes, it is well-structured and free of 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?

The tool has one nested parameter with no schema descriptions, no output schema, and no annotations. The description is only a fragment that fails to explain the payload's required structure, call destination format, or potential outcomes. This is clearly inadequate for safe and correct invocation, given the complexity of placing a call.

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?

The schema has no description for the 'payload' parameter (0% schema description coverage), and the tool description does not mention the parameter at all. The meaning of the parameter must be inferred entirely from the JSON schema, which only indicates it is an object with additional properties allowed, leaving the required structure and semantics completely undocumented.

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 uses the specific verb 'Initiate' and the resource 'WhatsApp call', clearly identifying the tool's function. This distinguishes it from sibling tools like get_calling_settings and update_calling_settings, which are about settings rather than initiating a call. However, it does not explicitly mention alternatives, so it falls short of a perfect score.

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 no guidance on when to use this tool compared to alternatives, no prerequisites, and no context for invoking a call. It is a single sentence with no usage direction, leaving the agent to infer when this tool should be selected over others.

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